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Battle.sol

pragma solidity 0.4.24;

import "zeppelin-solidity/contracts/token/ERC20/ERC20Basic.sol";
import "./CryptoFightsHero.sol";
import "./Managed.sol";
import "./interfaces/IBattleAction.sol";

contract BattleCore is Managed {
    struct Battle {
        uint16 turnCounter;
        // stuff
    }

    Battle[] public battles;

    event ChallengeCreated(
        uint battleId,
        uint challengerId,
        uint opponentId,
        uint8 minOpponentLevel,
        uint8 maxOpponentLevel
    );

    function createChallenge (
        uint _fighterId,
        bytes32 _randomHash,
        bytes32 _itemHash,
        uint _opponentId,
        uint8 _minOpponentLevel,
        uint8 _maxOpponentLevel
    ) public {
        // create challenge
        battles.push(Battle());
        uint battleId = battles.length;
        emit ChallengeCreated(
            battleId,
            _fighterId,
            _opponentId,
            _minOpponentLevel,
            _maxOpponentLevel
        );
    }

    event ChallengeAccepted(
        uint battleId,
        uint opponentId
    );

    function acceptChallenge (
        uint _battleId,
        uint _fighterId,
        bytes32 _randomHash,
        bytes32 _itemHash
    ) public  {
        // accept challenge
        emit ChallengeAccepted(_battleId, _fighterId);
    }

    event ChallengeWithdarwn(
        uint battleId
    );

    function withdrawChallenge (
        uint _battleId
    ) public {
        // withdraw challenge
        emit ChallengeWithdrawn(_battleId);
    }

    event BattleStarted(
        uint battleId,
        uint firstMoveFighterId
    );

    function rollInitiative (
        uint _battleId,
        bytes32 _randomHash,
        address[3] _items,
        bytes32 _proofOfWork
    ) public {
        // roll initiative

        // once both players have responded determine first move
        uint fighterId = calculateIniative();
        emit BattleStarted(_battleId, fighterId);
    }

    event ActionRegistered(
        uint battleId,
        uint fighterId,
        uint16 turnCounter,
        address action
    );

    event ActionResolved(
        uint battleId,
        uint fighterId,
        uint16 turnCounter
        // battle state
    );

    // this could be split into two functions.
    // next _randomHash is submitted automatically by client to resolve previous turn
    // without waiting for the player to choose their next action
    function applyAction(
        uint _battleId,
        uint _fighterId,
        uint16 _turnCounter,
        bytes32 _randomHash,
        address _action
    ) public {
        Battle storage battle = battles[_battleId];
        // calculte outcome of previous player's turn action
        emit ActionResolved(_battleId, _fighterId, _turnCounter); //, battle state);

        battle.turnCounter++;

        // register current player's turn action
        emit ActionRegistered(_battleId, _fighterId, battle.turnCounter, _action);
    }
}

L78:
Here you're using a 3 size array with item ids.

On L27, the hash is for these same 3 items, right?

L102:
this could be split into two functions. next _randomHash is submitted automatically by client to resolve previous turn, without waiting for the player to choose their next action

Yes, we should break it up like that