Meltdown

Description
All enemies with Frost are hit for 60 damage, and a Flame is left on their tile.

Strategy and Synergy
Meltdown synergizes with spells that apply Frost, especially those that apply it on multiple targets such as Blizzard. However, without any way to apply Frost - Meltdown is useless.

It is important to be aware of how many Frost applications your target has, as Frost clears itself every third Frost stack.

On the other half of it, Meltdown can also benefit from spells that synergize with Flame, such as Bushfire and Combust, although this is much less necessary than Frost synergies.

Trivia
A "meltdown" typically refers to a disaster, or a personal breakdown. However, in this case it is a bit more literal.