Oppy, the Persuasive

When Oppy, the Persuasive enters the battlefield choose another player other then you. You and
that player are in a contract.
{g/u}{g/w}{w/u},{t}: Create a contract token with "When
Contract enters the battlefield, write a contract.
You and the chosen player have to agree with it.
When this card leaves thebattlefield, the contract
is broken." and "If the contract is broken, the
player who broke it loses the game."