Crucio

The spell inflicts pain upon the target creature as red crackling lightning spreads from the spellcasting focus to the target. The target is swarmed with red sparks as their body undergoes searing pain. The creature takes 1d10 + spell modifier points of psychic damage and becomes paralyzed for 4 turns, the target creature makes a Wisdom saving throw each turn to reduce the damage in half. If reduced to 0 hit points, the creature is unconscious but stable. The target can be awoken the next turn.

At character level 13 this spell deals 2d10 damage for 5 turns, at level 17 deals 3d10 damage for 6 turns, at level 20 this spell deals 4d10 for 7 turns.