My first letter is in ocean but never in sea.
My second's in wasp but never in bee.
My third is in glider and also in flight.
My whole is a creature that comes out at night.
What am I?
As destructive as life, As healing as death; An institutioner of strife, Just as prone to bless. It is all that is good, Yet with an evil trend; As it was the beginning of things, It can also be the end. What is it?