Unknowable Mischief

You channel the forces of chaos so strongly that not man nor god can read your intentions. When you cast this spell, you choose any effect of any spell 5th level or lower and a trigger, revealing neither to the DM. (The creator of this spell recommends writing both down on a folded piece of paper for honesty’s sake.) If the trigger occurs within the next 8 hours of casting this spell, the effect goes off and your mischief is revealed, using the spell effect you chose in the casting of this spell. If this effect requires a saving throw, the save DC is your spell save DC.

When you cast this spell at 8th level or higher, you may choose a spell effect from an extra level higher for each level you upcast.