Wisps are powerful, magical entities of nature closely aligned with the Night Elves. So close is this connection that, it is believed, sometimes when a Night Elf dies, their spirit takes the form of a wisp. Wisps are able to become Ancients, grow plants such as trees with incredible speed and grow buildings out of trees. Wisps can also explode, causing damage to any enemies around them.
Wisps, first and foremost, protect nature and secondly, serve the will of the Night Elves. The reasons behind this obedience is unknown, but because of it wisps can be seen guiding Night Elf ships, growing settlements for them from the trees and performing other tasks.