Inco for Games

Card games, raffles, and hidden roles all need the same thing: state that stays secret until the rules say otherwise. A deck no one can predict. A hand only its owner sees. A reveal at showdown that everyone can trust. The ConfidentialDeck template gives you that as one base contract. You inherit it and write only your game rules. The shuffle, the private deals, the public reveals, and trustless settlement come with it.

Play the live demo

All four games running on Base Sepolia. Connect a wallet and play.

It is built on Inco Lightning v1. Inco is confidential compute for the EVM, not FHE and not zk. “Secret” means the value is decrypted by Inco. “Provably fair” means a covalidator attestation, not a proof.

The five moves

Everything confidential is one call on ConfidentialDeck.

Move	Kit call	Under the hood
Shuffle	`_newShuffledDeck(n)`	`e.shuffledRange(1, n+1, ETypes.Uint256)`, one Inco op
Draw	`_draw()`	`e.getEuint256(deck, i)` plus auto `allowThis`
Deal (private)	`_dealTo(player)`	`card.allow(player)`, only they can decrypt it
Reveal (public)	`_revealCard(c)` / `_dealFaceUp()`	`e.reveal(c)`
Settle	`_verifyValue(c, value, sigs)`	`e.verifyDecryption(...)`, bound to the handle

A whole game in about 15 lines

Inherit the kit and write only your rules. This is a simplified sketch; the real War.sol adds matchmaking and settlement.

import {euint256} from "@inco/lightning/src/Lib.sol";
import {ConfidentialDeck} from "./kit/ConfidentialDeck.sol";

contract War is ConfidentialDeck {
    mapping(address => euint256) public myCard;

    function startRound() external payable {
        require(msg.value >= deckFee(52), "fee");
        _newShuffledDeck(52);
    }

    function draw() external {
        myCard[msg.sender] = _dealTo(msg.sender); // only the caller can peek it
    }
    // showdown: reveal both cards and settle with _verifyValue(...)
}

The frontend half reads cards back.

import { getZap, peekMyCards, decodeCard } from "./client/incoDeckClient";

const zap = await getZap({ local: true });
const [c0] = await peekMyCards(zap, wallet, [handle]);
console.log(decodeCard(c0.value).label); // e.g. "A♠"

What is in the box

The ConfidentialDeck kit

The five confidential moves, the fees, and the rules that break new projects.

Worked examples

Four full games: War, Blackjack, Raffle, and Mafia.

Run it

Install, test against a local node, deploy, and wire the frontend.

Source

The full Hardhat project plus a Next.js demo dApp that plays all four games.

Building with an AI assistant? First set it up with Build with AI, the Inco agent skill that gives your assistant game-design sense. Then hand it the template: the repo ships an AGENTS.md explaining the kit, the per-game privacy model, and the frontend, so it can start fast.

More Inco games

More full game apps, built on Inco but not on the deck template. Read them for different confidential patterns.

Incasino

A six-game casino powered by e.rand(). The cleanest look at the play-then-settle pattern.

Mines

Minesweeper with an encrypted board. Bombs placed by one shuffle, O(1) per click, attested cashout.

Hangman

The secret word stays encrypted on-chain. Every guess is resolved with core encrypted operations.

Overview

ConfidentialDeck Template

More Games

Play the live demo

The five moves

A whole game in about 15 lines

What is in the box

The ConfidentialDeck kit

Worked examples

Run it

Source

More Inco games

Incasino

Mines

Hangman

Play the live demo

​The five moves

​A whole game in about 15 lines

​What is in the box

The ConfidentialDeck kit

Worked examples

Run it

Source

​More Inco games

Incasino

Mines

Hangman

The five moves

A whole game in about 15 lines

What is in the box

More Inco games