Volcano's Heart

This spell is a part of the Fire Streak spell chain and is found in the Fire Streak rune stone.

With this manipulation, you use super-heated air to encase the target. You then encase the target in an orb of unstable magma and fire. For the duration of the spell the target is locked into the orb, unable to act, while receiving 1d% damage per round. On the target’s turn in the final round of the spell’s duration, the orb explodes, dropping the target to the ground in whatever state the target is in. The target receives an extra 4d20 damage from the explosion and being dropped to the ground. If the target is still alive the target is stunned for 1d3 rounds.