Hydra
What is your strategy for confronting the fantasy creature Hydra in Dungeons & Dragons?
Types:
Pyrohydra
Cryohydra
More info on this creature: Source 7
Looks like a well placed fireball or two would go a long way with these baddies. Or some other kind of AOE spell of relative strength. Other than that go in guns blazing and wait for the heads to attack. It is a lot easier to hit them when they attack.
Likewise I am thinking some kind of greek fire would be a nice grenade like weapon to use.