Crown summoned too many octopi
Is there a way to clear the octopi army without restarting the level? This exact scenario is difficult to get out of with teleport and jump.
Black demons is the only spell that can kill friendly summons. You don't have it yet, but you can find the Black Magic Grimoire in the hole, which unlocks the Black demons and Obsidian wall spells.
Unfortunately, you're probably stuck without it, since you said teleport and jump are ineffective. Have you also tried to slow down time?