yoink

Original：🇺🇸 English
Translated

Play Yoink, an onchain capture-the-flag game on Base. Yoink the flag from the current holder, check game stats and leaderboards, view player scores, and compete for the trophy. Uses Bankr for transaction execution.

3installs
Sourcebankrbot/skills
Added on

NPX Install

npx skill4agent add bankrbot/skills yoink

Tags

Translated version includes tags in frontmatter
onchain-gamebase-chainsmart-contractcapture-the-flagbankr

SKILL.md Content

View Translation Comparison →

Yoink

Play Yoink, an onchain capture-the-flag game on Base. Yoink the flag from the current holder to start your clock. The player with the most total yoinks holds the trophy.
Contract: 
0x4bBFD120d9f352A0BEd7a014bd67913a2007a878
on Base (chain ID 8453)

Game Rules

  1. Yoink the flag - Call 
    yoink()
    to take the flag from the current holder
  2. Cooldown - You must wait 10 minutes (600 seconds) between yoinks
  3. No self-yoink - You cannot yoink from yourself
  4. Accumulate time - While you hold the flag, your time score increases
  5. Compete for trophy - The player with the most total yoinks holds the trophy (token ID 2)
  6. Track yoinks - Your total yoink count is tracked separately from time

Contract Interface

RPC template:
bash
curl -s -X POST https://mainnet.base.org -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_call","params":[{"to":"0x4bBFD120d9f352A0BEd7a014bd67913a2007a878","data":"SELECTOR+PARAMS"},"latest"],"id":1}' | jq -r '.result'
FunctionSelectorParamsReturns
yoink()
0x9846cd9e
-(write)
lastYoinkedBy()
0xd4dbf9f4
-address
lastYoinkedAt()
0x6a99616f
-uint256 timestamp
totalYoinks()
0xa5d0dadd
-uint256
topYoinker()
0x6a974e6e
-address (trophy holder)
mostYoinks()
0xd2d7774a
-uint256 (record)
COOLDOWN()
0xa2724a4d
-uint256 (600)
score(address)
0x776f3843
addr (32B padded)(yoinks, time, lastYoinkedAt)
balanceOf(address,uint256)
0x00fdd58e
addr + tokenIduint256 (FLAG_ID=1, TROPHY_ID=2)
Encoding: Addresses are zero-padded to 32 bytes. 
score()
returns 96 bytes (3 × uint256).

Yoinking

Use Bankr's arbitrary transaction feature:
{
  "to": "0x4bBFD120d9f352A0BEd7a014bd67913a2007a878",
  "data": "0x9846cd9e",
  "value": "0",
  "chainId": 8453
}

Errors

ErrorSelectorMeaning
SlowDown(uint256)
0x58d6f4c6
Cooldown not elapsed. Param = seconds remaining.
Unauthorized()
0x82b42900
You already hold the flag.
Cooldown check: 
current_time - lastYoinkedAt() >= 600

Workflow

  • Query 
    lastYoinkedBy()
    and 
    lastYoinkedAt()
    to check status/cooldown
  • Ensure cooldown elapsed (600s) and you're not current holder
  • Submit yoink transaction via Bankr
  • Verify with 
    lastYoinkedBy()
    or 
    score(address)

Resources