Rules, mechanics, stack

Visible field is 10 × 20 with two hidden spawn rows above. Seven tetrominoes deal from a shuffled bag. A ghost marks the landing row. Hold parks one piece; specials lose their curse when held.

Field

10 columns × 20 rows (+2 hidden)

Deal

7-bag, no triple-repeat of the same cat

Gravity

900 ms at L1, −72 ms per level, floor 70 ms

Lock delay

520 ms, up to 15 resets

DAS / ARR

160 ms delay, 38 ms repeat

Left / right

← → or A / D

Soft drop

↓ or S · +1 per row

Hard drop

Space · +2 per row, locks on landing

Rotate

↑ or Z / X / W

Hold

C · once per piece

Pause

P

On a phone the same six actions sit under the well. Soft drop is a press-and-hold; the rest are taps.

Line clears scale with level. Combos add on top. A small clock bonus ticks while the run is alive.

Single

100 × level

Double

300 × level

Triple

500 × level

Quad

800 × level

Combo

+50 × combo × level

Clock

+10 every 10 seconds

Level

every 10 lines

After 120 points a cursed piece can spawn (~16% roll, with a score- scaled cooldown). They are the original specials: same sprite, black fur, a rule that fights you.

Still

UNROTATABLE — spin is dead

Lazy

UNMOVABLE — no slide left or right

Pounce

HARD DROP — slams itself every frame

Hold strips the curse. The next piece from the bag is ordinary again.

A run ends when a cat locks above the well. Post it with a handle. The shared board stores every score. If a wallet is connected the same run is signed with personal_sign (EIP-191) and sent to the keeper for the on-chain board.

Epoch

15 minutes (900 s)

Winner

highest posted score in the window

Prize

60% of that epoch’s vault harvest, in ETH

Drip

30% merkle-claimed by $CATRIS holders

Team

10% to the team wallet set at deploy

Client is TanStack Start + React 19 + Tailwind. The well is a canvas painter: original cat SVGs preloaded as blob URLs, drawn with the js13k overflow math so ears and tails spill the cell. Scores live in Postgres (Neon in prod, PGLite locally). Chain reads go through viem on Robinhood Chain.

Chain

Robinhood Chain 4663

RPC

https://rpc.mainnet.chain.robinhood.com

Launch

letscash.fun · 3% trade tax

Factory

0x5bd1Fbe78a78fe8236fa00CF48fbEBA74ae34661

Hook

0x75A54357D9C78a2Db19004a5FDc76c50F9242AEC

Ticker

CATRIS

Traders pay the 3% tax in ETH on the Uniswap v4 pool that letscash.fun opens at launch. No bonding curve. The creator stream is handed to the vault.

trade $CATRIS → 3% letscash.fun tax → hook claim → Vault 60 / 30 / 10 → epoch winner ETH, holder drip, team

Two helpers, Solidity 0.8.24, Remix, 200 optimizer runs. Vault holds the pot and the split. Board holds epochs and signed scores. A 15-minute keeper harvests the creator stream, posts the winner, and publishes the drip merkle root.

1. CatrisVault(teamWallet) — letscash.fun creator stream recipient. Download
2. CatrisBoard — no constructor args. Download
3. Vault: setBot(keeperEOA), then setMetadata("https://catris.xyz", "catrisXYZ", "https://github.com/catrisXYZ", "https://t.me/catrisXYZ").
4. Board: setBot(keeperEOA), setVault(VAULT_CA).
5. Launch on letscash.fun/launch: name Catris, symbol CATRIS, fee 3%, pair ETH. Then hand the creator stream to VAULT_CA with updateCreator and call setTokenCA(TOKEN_CA) on the vault.

Bot source: epoch-bot.mjs + package.json. Env: RPC_URL, BOT_PRIVATE_KEY, VAULT_CA, BOARD_CA, TOKEN_CA, MIN_CLAIM_ETH. Fund the keeper with ~0.1 ETH for gas.

After deploy set VITE_VAULT_CA, VITE_BOARD_CA, VITE_TOKEN_CA, VITE_KEEPER_URL. Until those exist the arcade still runs — scores live on the shared board, chain writes wait for the keeper.

• Empty escrow no longer reverts — the keeper can poke claimFromEscrow every epoch.
• Reentrancy lock on prize, drip, team, and escrow pulls.
• Score signatures are personal_sign, the message wallets actually produce.