Mechanism LabONCHAIN MECHANICS
Learning tools

Learning toolsThese tools appear when the journey reaches them, or you can open them directly here.

Value pathAfter several mechanisms, inspect how value and risk cross boundaries.LabLeave the lesson prompts and freely change or break the mechanism.ChallengesUse cross-module questions to test whether the boundaries really hold.GlossaryLook up unfamiliar terms and return to the related lesson.Research journalSave experiment states, compare outcomes, and write your explanation.
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Prediction market sandbox

There is no single correct route. Change orders, liquidity, and resolution to watch price, collateral, and positions move together.

SIMULATION ACTIVE
Binary event market · Normal market

Will humans return to the Moon before 2028?

Quotes cluster around 68–72, with buyers and sellers on both sides.

TradingOPEN
Tune beliefs, then watch orders

A belief does not become a trade by itself; the market only sees a price, quantity, and budget in the order book.

Subjective view
YES implied price68/ 100

Best bid 68Best ask 72Spread 4

Locked collateral200credits
Your available balance2000credits
Open interest2contracts
Coach

The order entered the public book. It may fill immediately or wait if it does not cross the spread.

YES order bookPrice / quantity

BIDS

Alice681

ASKS

Carol724
BUY NO @ q appears as SELL YES @ 100−q
Accounts and positionsCredits / YES / NO
AAlice1796 (+68 reserved)20
BBob1936 02
CCarol1888 (+112 reserved)00
你You2000 00
Event log6 EVENTS
  1. 06

    Carol submitted: BUY NO 4 shares, max 28 credits.

  2. 05

    200 credits locked in the settlement contract.

  3. 04

    Trade matched between Alice and Bob: 2 shares, YES 68, NO 32.

  4. 03

    Bob submitted: BUY NO 2 shares, max 35 credits.

  5. 02

    Alice submitted: BUY YES 3 shares, max 68 credits.

  6. 01

    Market created: Will humans return to the Moon before 2028?

Oracle and resolutionReliable source

Choose the result the oracle will finally write. In the wrong-oracle scenario, deliberately choose the opposite of reality.

✓

System checksAll invariants hold

ACTION HISTORYExperiment timeline
1 state snapshots

Use the slider to return to an earlier step. Continuing from there replaces the later history with a new sequence.

Initial state
View experiment records →

Not sure where to start? Try these four experiments.

01

Choose thin liquidity, push the YES price toward 90, and inspect how much actually fills.

02

Submit an order that does not fill immediately, then cancel it from the book.

03

Resolve the same positions as YES and NO and compare final balances.

04

Switch to the wrong oracle: price can look reasonable while settlement is completely wrong.