How to Play Oil Rock

Oil Rock rules: how to play in two minutes

Oil Rock is an economic worker-placement board game from Cranio Creations, designed by Marco Piola Caselli. In four rounds, you run an oil company: place workers on a changing action wheel, drill three oil wells, refine barrels into economic rewards and spread your railway and offices across Pennsylvania-inspired regions. The company with the most Victory Points after round four wins.

Each round has six phases, but you only get three normal Worker placements in the Actions phase. An Assistant activates one action; a Manager can perform one action or link two connected actions on the inner wheel. Then all companies extract their oil, activate refineries, claim round-specific Milestone points and prepare for the wheel to rotate.

The most important production loop is Drill → Extract → Refine → Improve. Wells produce barrels at the extraction phase, not immediately every time you build a Drill. Refineries consume barrels to provide resources, Patents, Progress or points. Advancing on the Progress track upgrades your Character notebook, future income and available worker mix.

Rules reference: Cranio’s official account published an English Oil Rock rulebook and separate appendix in the BoardGameGeek Files library. The publisher’s description independently confirms the four-round, six-phase structure. This page explains the framework and commonly missed interactions; use the official file and the icon on a physical tile for edge cases. For game overview, player fit and editions, see our Oil Rock game hub.

The six phases of an Oil Rock round

Example of correct timing: in round one, you build a Drill during Actions. After all players finish placing Workers, the extraction phase checks every well’s current depth, including the new Drill you just built. You then spend the produced barrels on Refining, receive Milestone points and prepare for round two. You do not get an extra worker-placement phase just because the wheel rotates.

There are exactly four rounds in the published game. An engine that will not pay back until a hypothetical fifth round has no fifth extraction phase available. That is a major part of how to value costly investments.

Oil Rock setup checklist for 2, 3 or 4 players

Oil Rock has a substantial table presence. A clean setup helps players understand which pieces are personal and which are shared. Use the publisher’s printed diagram for the exact placement and orientation of individual action tiles.

1. Prepare the shared board. Put the main board in reach of all players, including the Progress track, Victory Point track, Region network, Milestone row and Improvement market.
2. Assemble the action wheel. Fit the inner and outer parts for your player count; the number of slots per ring is 5 at two or three players and 6 at four players. Place the appropriate action tiles randomly in the permitted spaces.
3. Populate the map. Shuffle the 12 Region tiles and place them faceup. Put the corresponding Railway Bonus tokens on their marked spaces.
4. Reveal round goals. Shuffle Milestone tiles, reveal four and set aside the unused tiles. There is one scored Milestone per round.
5. Build the Improvement market. Reveal 6 cards for two players, 7 for three, or 8 for four, in the designated numbered arrangement. Keep the rest as the draw deck.
6. Prepare each company board. Each player receives the relevant Drills, Offices, Turbines, Refinery and Briefcase tiles, Extra Action tiles, three Assistants, three Managers, a Train and an Engineer. Organize numbered Refinery tiles in order.
7. Set turn and Progress markers. Randomize initial player order, position scoring markers and stack Progress markers as specified in reverse turn order.
8. Choose Characters. In reverse turn order, players choose among a pool of one more Character notebook than the number of players; each begins on its Level I side.
9. Distribute opening resources. Everybody gets one Tool, one Coal and one Coin. Second player gets one extra Coin, third gets one extra Tool and fourth gets one Patent.
10. Position the trains. In reverse turn order, place each Train and Engineer together in a different yellow Plains Region, immediately taking its Railway bonus.

Before starting: confirm that each player understands their three normal placements and how their Character notebook dictates the mix of Assistants and Managers. The box contains several of each type, but that does not mean all six available pieces are placed in every round. For a component-by-component setup reference, consult the Oil Rock setup checklist against the official rulebook.

Assistant versus Manager: what changes?

Every round each player normally places three Workers, in the order prescribed by their Character level: use Assistants before Managers. An Assistant is a straightforward one-action piece; a Manager is more flexible, but must be positioned correctly to link actions.

Worked example: one Manager, two connected actions

Suppose two adjacent inner-ring tiles let you advance Progress and buy an Improvement. You place a Manager to activate both legally connected actions. First you complete the Progress action, including its costs and possible Character-level benefit. Then you complete the Improvement purchase using the resources and board state now available. If the first action leaves you unable to pay the second, you can decline it; you do not receive the second tile’s printed benefit for free.

Do not confuse the six phases with six worker turns. Players take three regular placements during Phase 2. The Extraction, Refining and Milestone phases are not additional Assistant or Manager placements, although Patent spending and specific effects can create limited extra opportunities.

How the rotating action wheel works

The wheel is the central competition for action access. Its action tiles are randomly arranged in setup within the slots allowed for your player count. Workers occupy locations when used. After each round, the outer ring rotates one space clockwise, changing the relative positions of actions and which linked opportunities Managers can use.

Some spaces are on the inner ring; these matter for a Manager’s two-connected-action option. Other positions provide a single action. The icon and full text on the particular tile are the final authority on its cost and reward.

How do you plan around a wheel that changes?

• This round: identify which actions provide resources and which consume them, then decide whether a Manager can combine a supply action with a development action.
• Opponent interference: check whether another player can take or block your preferred tile first. Copy may provide a backup route at the cost of Progress.
• Next round: because the outer wheel rotates, a combination available now may not exist in exactly the same shape again.
• Your Character level: its worker composition and benefits can make a linked inner-ring option stronger in later rounds.

Example: if you need Coal to pay for a Turbine, a Manager link that acquires Coal and then builds the Turbine is attractive. But if that Turbine will not be adjacent to a Refinery you can actually operate, the two-action sequence may be technically efficient but economically poor. Evaluate the result, not merely the number of activations.

Copy action rules: paying Progress to imitate a tile

Oil Rock has a Copy action that can preserve options when the wheel’s direct spots are inconvenient. Spend one Progress, choose any Action tile not occupied by one of your own Workers, and carry out that tile’s action under its normal cost and requirements.

Does the copied tile have to hold an opponent’s worker? No. The published wording allows an unoccupied tile. If an opponent does occupy the tile being copied, that opponent gains one Progress as compensation; when nobody occupies it, nobody receives that compensation. This is also documented in community rules discussions with Cranio’s official account. Oil Rock rules FAQ.

Worked example: copy versus blocking

Your desired Drill action tile is occupied by a rival, but not by one of your own pieces. You can pay one Progress to copy it and construct the legally permitted Drill, paying that Drill’s normal cost. Your rival receives one Progress for occupying the copied tile. If the tile had instead been empty, you could still copy it, but nobody would receive a compensation Progress.

The Copy action is not a waiver of action costs, a license to activate a forbidden tile, or a second Worker placement. It is often useful for flexibility, but sacrificing Progress can delay a Character upgrade or reduce future scoring.

What can you do on the action wheel?

Every wheel action has its own cost and icon. Rather than memorizing the action tiles as unrelated effects, organize them by what part of the economy they improve.

How many pieces can one build action place? Normally one of the specified type. A publisher-confirmed ruling explains that being able to afford several Offices, Drills or Turbines does not let a single construction action build several pieces. A separate effect expressly granting another build is different. This distinction prevents accidental engine acceleration.

Some Action tiles offer special effects or multiple defined choices. Follow the physical tile when a general category above does not capture its full effect; the table is a teaching reference, not a substitute for every numbered Action tile in the appendix.

Train and Engineer movement: a practical guide

Your Train moves over connected Regions on the shared map. A normal move goes one or two connected Regions, paying the Coal terrain cost of each Region entered. Take the Railway bonus for arriving in a Region as instructed.

After moving the Train, you can move your Engineer to a Region on the route or leave it where it began. A special movement effect may send the Train directly to another Region, paying the destination’s terrain cost and collecting that destination’s Railway bonus; its Engineer options are described by that effect.

Why move the Engineer at all?

The Engineer matters because an Office may be built where your Train or Engineer is present. Separating them can preserve access to a useful Office location while the Train continues gathering bonuses elsewhere. But terrain costs and railway connectivity still matter for legal movement.

Worked movement example

Your Train moves through one adjacent Region and then a second, paying the required Coal for each terrain entered and collecting the applicable Railway bonuses. You then leave your Engineer at the first Region rather than bringing it all the way to the second. On a later Office action, you may have a legal building location at either unit’s Region, provided all other Office requirements are met.

Restrictions: a single normal movement action cannot revisit the same Region in a loop. You also cannot skip paying entry costs merely because the Train has been to the area earlier in the game. Consult the board’s actual connections and tile costs rather than calculating distances in straight lines.

Building Offices: costs, spaces and branch bonuses

Offices establish your company’s geographic presence. Your Train or Engineer must be in the relevant Region. A typical Office build costs 2 Tools on Plains, 3 on Hills or 4 in Mountains, according to the Region’s terrain. You then place one Office in an eligible open position and resolve that Region’s branch bonus as specified.

You can have at most one of your Offices in any single Region, and your company has a total supply of six. A Region cannot hold more than three Offices. If there is no legal space or you cannot pay the cost, you cannot build there just because one of your units is present.

Office placement affects both short- and long-term play: the immediate branch reward may advance your economy, while the printed position contributes Victory Points at the end. The Office supply on the company board can also interact with built Drills, so manage the pieces carefully rather than placing them interchangeably.

Example decision: a Plains Office costs fewer Tools than a Mountains Office. But if your Train is already in a Mountains Region with a valuable bonus or an important scoring slot, the more expensive placement might still be worthwhile. Compare the full return—including any railway movement needed—with the action and material cost, rather than choosing the cheapest Office automatically.

Drilling wells: what do yellow, green and blue mean?

Every player has three oil wells on their company board. They correspond to three barrel grades: yellow (lower), green (middle) and blue (higher). A Drill action places one Drill in the next legal position of a well, deepening that shaft and improving the amount or grade of oil it will produce at the extraction phase.

Each shaft has a limit of three added Drills. Follow the printed costs and legal next position; you cannot leap directly to an advanced depth just because you have enough tools for the whole shaft. Some Drill positions initially carry an Office piece that must be removed or relocated under the relevant rule before the Drill can be placed there.

Drilling does not automatically activate a Refinery. The timing is important: you place the Drill during the Actions phase, then extract during Phase 3 and refine during Phase 4. That gives you time to construct or improve a refinery before the same round’s production resolves.

Higher-grade production becomes valuable when it matches the recipes on the Refineries you built. Building all three wells equally is not automatically optimal if your refineries overwhelmingly consume one grade; equally, focusing on only one shaft may leave you with unused refinery capacity. This is a planning trade-off, not a publisher-prescribed build order.

Oil Extraction: how many barrels do you receive?

During Phase 3, each well produces oil based on the depth it has reached. Read the barrel production shown at that well’s current Drill level on your own company board. Receive the corresponding physical barrel tokens for yellow, green and blue oil.

For many purposes, better oil can substitute for a lower grade: a blue barrel can satisfy a green or yellow requirement, and green can satisfy yellow. The reverse does not work: yellow cannot automatically meet a requirement for blue. A specific tile can introduce further conditions, so follow its printed recipe.

Simple substitution example

Suppose a Refinery asks for one green barrel, but your inventory is two blue barrels and one yellow barrel. You may spend a blue barrel as the required green, subject to that Refinery’s other instructions. The yellow barrel cannot replace green. This illustrates the quality substitution rule, not a particular real Refinery tile.

After the refining opportunity, you normally keep a maximum of one barrel of each color for the next round, discarding surplus barrels without compensation. That makes it wasteful to pursue large production without enough conversion outlets. Production volume matters only when it can be processed or otherwise exploited.

Oil Refining: recipes, the basic refinery and Turbines

In Phase 4, you can activate your built Refineries in the permitted order, each at most once per round. Pay the barrel recipe on each Refinery to gain its printed reward. Depending on the Refinery, that reward can include Tools, Coins, Coal, Patents, Progress and Victory Points.

Turbines increase production when positioned next to an active Refinery. The Turbine’s bonus belongs to the adjoining Refinery activation, not to an unrelated building elsewhere on your company board. Turbines are placed beside a Refinery and cannot be moved freely afterward, so choose that relationship deliberately.

How does the basic Refinery work?

The basic Refinery accepts any mix of barrels. Each yellow barrel is worth 1, green 2 and blue 3 units of raw value. Add the values and divide by two, rounded down, to determine the number of standard resources it produces. You can take those as Tools, Coins or Coal under the basic refinery rules.

Worked example: value and rounding

You send one blue barrel and one green barrel to the basic Refinery. Together they are worth 3 + 2 = 5. Half of five, rounded down, is 2 resources. Adding another yellow barrel makes the total 6 and increases the output to 3 resources. A single yellow barrel would convert to zero through that basic formula, so wait or find a better use where possible.

Important: do not multiply all Refinery rewards by the number of Drills or assume every Turbine boosts every Refinery. Production follows each specific recipe, each activation limit and each connected Turbine’s printed effect.

Improvement cards: Equipment, Technology and Structures

The Improvement market offers three functional categories. When taking an Improvement action, pay a displayed card’s printed cost, add it to the matching location on your company board and apply its category’s effect. Card availability depends on the shared market; it does not refresh after every purchase.

After placing an Improvement, you may receive points for the barrel spaces exposed in the corresponding shaft row. This rewards the developing shape of your company board as well as the purchased card’s printed effect.

At round end, remove the two lowest-numbered Improvement cards remaining in the display, then refill to the player-count limit—6/7/8 for 2/3/4 players. The market is therefore time-sensitive. A card that appears early may be gone before you have enough resources if it remains among the lowest numbers.

Practical lesson: a yellow ongoing Improvement can pay back over several subsequent rounds; a green card can solve an immediate resource shortage; a blue Structure asks whether your development path will satisfy its scoring condition. None is automatically best just because of color.

Progress track, Character notebook and turn order

Progress has several jobs. It improves your Character over time, unlocks more capable actions or income, helps determine next round’s player order, and contributes to endgame scoring. Spending Progress on Copy therefore creates an actual opportunity cost.

A Progress action typically advances your marker one space; you may buy up to four additional spaces for 2 Coins per extra space, advancing at most five spaces from that single action. Check level thresholds as your marker moves.

When you reach a new Character level, turn your notebook page forward to the corresponding side. This changes your displayed income and available abilities. At Level III, each Character has a distinct power. Your notebook does not flip backward if you subsequently spend or lose Progress.

What determines first player next round? At the end of a round, players are ordered with the company furthest behind on Progress first. A lower stacked marker is considered behind when positions tie. So progress can give better company benefits while also causing you to act later. This is a deliberate tension, not a scoring bug.

After reaching the top of the track, extra Progress converts to Victory Points as specified rather than unlocking unlimited new notebook levels. Apply the printed track limit and markers rather than assuming it cycles.

Patents, Briefcases and limited extra actions

Patents are a flexible special currency. A player can spend them to reveal and claim Briefcase rewards on their company board, or spend three Patents to use an unused Extra Action tile. The extra-action option is limited to one such use per player per round.

The timing is broader than the normal worker-placement phase: certain Patent spending is allowed during a player’s own turn and appropriate later phases, in the order set by the game. Do not treat this as unlimited open trading or spend Patents to trigger extra placements whenever a different player is acting.

Example: a fourth action isn’t free

You have three Patents and an Extra Action tile available. You can spend the three Patents for the permitted extra action this round. But those Patents would otherwise be useful for Briefcase rewards or one point each if left unused at game end. The extra action must therefore generate more value than what you give up; its worth is sensitive to the current round and development opportunities.

If an effect grants additional Progress or Patents, update your relevant tracks and supplies at the appropriate timing before resolving any dependent reward. Do not activate multiple Extra Action tiles in the same round just because you amassed six Patents.

Milestones and the end-of-round wheel rotation

Each of the four rounds has a visible Milestone objective. After Refining, check the active Milestone’s condition, score the indicated Victory Points and then remove or flip the resolved Milestone according to the setup. The next goal is now the one that matters for future planning.

At end of round, retrieve Workers, rotate the outer wheel one position clockwise, remove the two lowest-numbered Improvements from the market and refill it to the player-count limit. Update turn order using the Progress track; the player furthest behind in Progress acts first on the next round.

That rotation changes future action adjacency, so your current plan should not assume next round will offer the identical Manager pair. A sensible late-round decision can be to prioritize the Milestone only when the reward also builds an engine you will need next round.

Milestone planning example

Suppose this round rewards companies with deeper wells. You could use your last Worker to drill once more and earn Milestone points, plus more extraction and future final well points. But if that Drill has no affordable placement or produces oil that all your Refineries cannot process, a different action may still be better. The Milestone’s marginal value should be considered alongside every other benefit.

The printed objective tiles change from one match to another. This guide avoids inventing a universal milestone order or fixed Victory Point bonus for every possible condition.

Oil Rock endgame scoring: everything to count

Oil Rock ends after the fourth round. After its Milestone and normal round-end process, finish the final scoring categories on the company boards and applicable cards. The winner is the player with the greatest total Victory Points.

Original endgame scoring example

Imagine your three wells end at depths 4, 3 and 2. Their points are 10 + 5 + 2 = 17. Your occupied Offices contribute 14 more, and eligible Turbine-adjacent high-number Refineries contribute 7. Your blue Structures score 9, your final Progress position scores 5, and you have 4 unused Patents. Finally, you have 8 combined Coins, Tools and Coal left, worth 2 points in full groups of three. Your complete total is 58 points.

These values are an invented arithmetic teaching example, not a sample match or a promise that any particular collection of real scoring tiles gives precisely those Office and Structure values. Read your own player board and card faces to determine actual awards.

How do ties break? The player further along the Progress track wins the tie. When Progress markers occupy the same track space, the relative stacked marker position determines who is considered further ahead under the rulebook’s order. Do not use the number of Offices or remaining Coins as an unofficial first tiebreaker.

Two example turns that explain the engine

Example A: building a useful first-round oil loop

1. During Income, take the resources shown on your Character notebook.
2. On an early Worker placement, take a Drill action and deepen your yellow well.
3. On another placement, add a Refinery you can operate with that well’s output, paying its cost.
4. Use your third placement to develop your resources, Progress or a future Turbine as the wheel permits.
5. At Extraction, take the yellow barrels shown by the well’s final depth.
6. At Refining, spend eligible barrels to activate the Refinery and receive its printed reward. Then score the current Milestone.

The strength of this sequence is not the exact order, which the wheel might not offer. It is that production and conversion are ready in the same round, so your Drill does not produce barrels you have no use for.

Example B: investing in Company Progress rather than another Drill

You have enough resources to deepen a well, but your Character is one Progress space away from a level that will improve your next round’s income. A Progress action could unlock that benefit before the following Income phase. Since only four rounds exist, ask whether the saved resources and stronger workers in later rounds will exceed the additional oil output and final scoring from a Drill placed now. That is a trade-off between immediate production and future action efficiency.

Neither example is a fixed optimal opening. Real choices depend on the initial action-wheel arrangement, Character notebook, current Improvement display, and round goals.

Five beginner strategy principles for Oil Rock

• 1. Keep drilling and refining in balance. Extra barrels are not automatically points, and most surplus oil cannot be carried over. Build enough conversion capacity to use the grades you expect to produce.
• 2. Treat Managers as a sequence puzzle. Two linked actions are most useful when the first creates the materials or position needed by the second. Declining a bad second action is preferable to paying a cost for negligible value.
• 3. Watch the Character level before round two and three. Income and worker availability can improve for several remaining rounds. However, pushing Progress very late is less likely to repay through economy alone.
• 4. Turn railway movement into Office opportunities. A Train action may grant bonuses, place an Engineer strategically and make future Offices possible. Avoid aimless travel that does not connect to scoring or production.
• 5. Remember four different clocks. The four-round game timer, rotating wheel, changing Improvement market and current Milestone can all change what is valuable before you finish a plan.

These are editorial deductions from the published systems, not results from controlled playtesting. The designer’s September 2026 diary describes the choice to move from an earlier design to a wheel, the importance of four-round pacing and Milestones, which explains why turn timing is central to the game’s identity.

Common Oil Rock rules mistakes to avoid

• Placing six workers every round: the box includes three Assistants and three Managers per color, but you normally place three Workers per round using your Character-level mix.
• Using a Manager to activate two unrelated spaces: the double activation must meet the inner-ring connection rule.
• Building several identical pieces with one action: a standard construction action makes one Office, Drill or Turbine unless a separate effect grants another build.
• Taking oil as soon as a Drill is built: oil is produced in the shared extraction phase.
• Using yellow oil to replace blue: higher grades substitute downward, not lower grades upward.
• Activating the same Refinery repeatedly: each built Refinery normally operates at most once during a refining phase.
• Saving unlimited barrels: normally keep no more than one of each color after refining.
• Copying your own occupied action: Copy cannot target an action tile occupied by one of your own Workers.
• Assuming Copy must target an opponent: an empty tile is eligible, with no compensation paid.
• Giving everyone the same first-turn resources: later seats get the stated Coin, Tool or Patent compensation.
• Forgetting Market expiration: the two lowest-numbered Improvements leave the display at each round end.
• Building a Turbine with no useful adjacent Refinery: its bonus is associated with the adjoining Refinery activation.
• Ignoring Progress in a tie: the final tie-breaker is based on the Progress track.

When an edge case depends on a tile or particular improvement, consult the official English rulebook and rules appendix. This article is a teaching guide, not a comprehensive reproduction of every tile’s effect.

Oil Rock FAQ: fast rules answers

How many players does Oil Rock support?

Two to four players. Cranio Creations lists an approximate 90-minute play time and age 13+.

How many rounds are in Oil Rock?

Exactly four. Each round proceeds through six phases, followed by final scoring after the last round.

What are the six phases?

Income, Actions, Oil Extraction, Oil Refining, Milestones and End of Round.

How many workers can you place each round?

Three normal placements, with the Assistant/Manager mix determined by the current Character notebook.

What is the difference between an Assistant and a Manager?

An Assistant uses one action tile. A Manager can use one action or legally activate two connected inner-ring tiles.

Does the action wheel rotate?

Yes. Its outer ring moves one space clockwise at round end.

How do you take the Copy action?

Spend one Progress to use an action tile not occupied by your own Worker. An opponent occupying the copied tile gets one Progress.

Can Copy target an unoccupied tile?

Yes, under the current rules wording; no opponent earns compensation if the tile is empty.

Can I build several Drills with one Drill action?

Normally no. A build action constructs one piece of its type unless a separate effect explicitly grants another build.

When do you extract barrels?

During Phase 3, based on the final depth of each colored well after the Actions phase.

What are the three oil colors?

Yellow (low grade), green (middle) and blue (high grade). Blue can substitute for green or yellow; green can substitute for yellow.

How does the basic Refinery work?

Value barrels yellow = 1, green = 2 and blue = 3. Convert their total to Tools, Coins or Coal at half value, rounded down.

Can a Refinery activate more than once?

Normally no. Each built Refinery can be used once during a Refining phase.

What does a Turbine do?

It adds the printed output to an adjacent Refinery when that Refinery operates.

What are Patents used for?

They can unlock Briefcase benefits or pay for a limited extra action; unused Patents also score at game end.

How many Patents buy an extra action?

Three Patents permit one Extra Action tile, limited to one such extra action per round.

How do you determine next round’s turn order?

The player furthest behind on the Progress track goes first. Stacked markers resolve ties under the printed rule.

What scores at the end of Oil Rock?

Well depth, Offices, qualifying late Refineries, blue Structures, Progress, unused Patents and groups of three leftover basic resources, in addition to points scored during play.

How much do wells score?

Well depth 1/2/3/4 is worth 0/2/5/10 points respectively at game end.

How do you break a tie?

Compare Progress positions; the track’s stacked-marker ordering also matters if the spaces match.

Is there an official solo mode?

No official solo mode appears in the current 2–4-player rulebook or publisher specification.

Where is the English Oil Rock rulebook?

At the official rulebook file on BoardGameGeek, uploaded by Cranio’s official account. An appendix is available from the same file library.

Sources and editorial methodology

Primary publisher specifications: Cranio Creations — Oil Rock (2–4 players, approximately 90 minutes, 2026 release window and the game’s design). Oil Rock — Official Rulebook ENG and the companion English Rules Appendix are listed under the BoardGameGeek game’s Files, uploaded by the official BGGCranioCreations account.

Structured rules cross-check: Ludex setup, gameplay, teaching outline, scoring and FAQ. Ludex is an independent, unofficial rules reference that identifies the official rulebook as its underlying source. It is cited for numbers and interactions that are explained here in original language. Refer to Cranio’s original rulebook if any fan summary or printing differs.

Designer context: Marco Piola Caselli’s Oil Rock designer diary, published on BoardGameGeek by BGGCranioCreations (26 September 2026), for the design of the wheel, turbines, four-round length and milestones.

Editorial disclosure: This article is independently written, not a pasted rulebook or a claim of first-hand game testing. Worked examples and strategic suggestions are original illustrations, with invented example numbers where indicated. We did not reproduce the publisher’s copyrighted diagrams or tiles, and exact individual costs remain governed by your physical pieces. Last checked 1 November 2026. See our editorial policy and Oil Rock game overview.