Great Chaos Fireball (5e Spell)
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|Casting time:||1 action|
You evoke a powerful clump of hot chaos flame in your hand and hurl it. Make a ranged spell attack against a target within range, dealing 10d8 fire damage on a hit. Hit or miss, the flame then pools on the ground into a pile of lava. This lava covers a square area, 15 feet on a side, centered on the target. Whenever a creature starts its turn within the lava or crosses into the area for the first time on a turn, it must make a Constitution saving throw, taking 3d6 fire damage on a failed save, or half as much on a successful one.
The lava created by this spell cools and vanishes into nothing at the end of your next turn.