Binding Oath

An oath, agreement, or contract you have witnessed or signed becomes magically binding. 

This spell cannot affect those who do not agree to be bound by it when the spell is first cast; when the oath is first made, everyone involved must agree (even if unwillingly) to be  bound by the magic of the oath. An oath may be as simple as a few spoken words and a handshake, or as fiendishly complex as a Faustian pact written and signed in blood. The terms of the oath generally extend to a year and a day (366 days), unless a shorter span of time is agreed upon by both parties.

Agreements can be between the spellcaster and a second party, or ratified between two or more parties with the spellcaster acting as arbiter. Up to two individuals at a time can be included in the contract or agreement.

Those who attempt to break the terms of the agreement by action or inaction must make a Wisdom saving throw; upon a failure, they must continue to do everything in their power to keep their oath, and they cannot attempt to break it again for 24 hours. If they succeed on the Wisdom saving throw to break their oath, they immediately take 1d6 Psychic damage and are Stunned for 2 rounds as a consequence of breaching contract or breaking their promises. 

A Binding Oath does not differentiate if it becomes impossible to keep the agreement; for example, if you promise magically to keep someone from harm, and that person is hurt or dies while you are in prison, you still suffer the Psychic damage and are Stunned as a result of the oath being broken.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, you can bind up to two additional creatures to the oath for each slot level above the 1st, and the psychic damage for breaking the oath goes up by 1d6 for each slot level above the 1st.