I have a creature capable of absorbing all energy to feed itself. So efficient is it at doing this that the creature itself appears utterly black, since it absorbs all visible light. Its eyes are like deep voids.
Even a spear thrown will impart kinetic energy, which the creature will use, and the creature can then convert the spear to energy and consume it. The creature is something of an energy vampire, it can suck the energy out of anything.
It can control its absorption of energy and redirect/output anything absorbed, thus allowing it to reproduce, fend off an attacker, etc.
How could my protagonists defeat such a being? Have I made it too powerful?
Notes: Magic is available, and so is advanced scientific knowledge. One of the protagonists is from an ancient race that has faced the evil before. One of the protagonists is a warrior. They're on a magical world, and don't have time to build an advanced scientific apparatus.
=== UPDATE ===
There's a lot of great ideas being given. Some of them I can't use, since I'm writing and releasing my story in serial fashion, and certain parts are already out.
The approach I'm going to take is this (which is a kind of amalgam of several suggestions):
- My sciencey character (he's a universe-hopping teddy bear, don't ask) will rush to build a portal. The portal will link to a negative-energy/zero-space universe, which will eventually kill the creature.
- My wizard will use a variety of energy-sucking spells (cold, etc), to draw energy away from the creature (which is currently partially imprisoned).
- My warrior will break the seals of the prison and act as bait, leading the creature to the portal.
- An army of squirrels (it's... complicated) will complete the process by forcing the creature through the portal.
With all the good suggestions made I'm having difficulty picking one to accept. So I'll leave this open for another couple of days, and then pick the answer with the highest votes.
So to everyone: vote for the answer you like best. :-)