Mana Scramble

The wizard raised his staff, and the air around him crackled with energy. He began to chant, and the words of power filled the room. But as he reached the crescendo of his spell, his voice faltered, and the magic twisted and turned, fading into the air. “What?! No!! I worked so many years on this ritual! What is happening?! What have you done?!” The wizard’s eyes widened in horror as he saw the sorcerer’s grin.

2nd-level Abjuration

Classes: Sorcerer, Wizard
Casting Time: 1 action
Range: 60 feet
Components: Verbal, Somatic
Duration: Concentration, up to 1 minute

Description:

You temporarily disrupt the magical flow of a target, scrambling their ability to cast spells. Choose one creature within range. The target must make a Constitution saving throw. On a failed save, any time the target attempts to cast a spell during the duration of this spell, they must roll 1d4. If the roll results in a 1, the spell fails and is wasted. If the roll is 2, 3, or 4, the target must cast another spell they know, chosen randomly from their available spell list, as if they had cast it instead of their intended spell. This substitution causes the effect of the randomly chosen spell to take place. The target cannot control this random spell selection, and it may cause unintended effects.

Any spells cast in this way do not consumes the original spell slot, and if it requires components that the target does not have, the spell fails. If the spell cast in this way requires concentration, the target automatically concentrates on the spell and can choose to end it at any time.

At Higher Levels:

When you cast this spell using a spell slot of 3rd level or higher, the duration increases by 1 minute for each slot level above 2nd.

At 5th level, If the 1d4 roll is 4, the effect is similar to rolling a 2 or 3, but additionally, a wild magic surge is triggered.

At 9th level, the duration becomes until dispelled by the caster or by a remove curse spell, greater restoration spell, or similar effect.