You place the palm of your hand on the creature that shares a language with you, envisioning the terms of a contract in your mind. It must contain two things: an objective for the target creature and/or yourself completable within the next 5 days, and a punishment's for each creature involved should they fail there objective (Neither of which need to be the same. The creature see the terms of the contract their mind and can choose to accept or decline the contract.
If the creature declines the contract, the spell fails to cast and the spells slot is not expended. The spell automatically fails if the target is already under the affects of a spell that controls their actions (such as the suggestion spell or this spell).
If the creature accepts the contract a runic mark is burned into the target's body and your body in a location of your choosing, which last for the duration of the spell,. Then if either creature fails to complete their objective, they must make charisma saving throw with disadvantage or be subjected to the punishment's you choose.
The punishment of this spell can do one of two things: Control the creature's actions or cause them to die. If the punishment you chose controls a creature's actions, it can only do so for 1 hour. If the punishment's you chose is death, the creature has a heart attack and instantly dies.
this spell is especially hard to dispel. If dispel magic is cast to remove it the effects of this spell, must be cast using a slot at least three level s higher then the spell slot used in order to success fully end it