Answer:
A mysterious, fantastic creature, It has one defining feature, And for humans at their worst, In their eyes it's just a horse
With four oars it swims but it is always at home. Its back is like armor, tougher than chrome. What is it?
They don't forget.
Even if my life is taken eight still remain.
Looks like a hippo crossed with a unicorn.
I'm the source of all emotion but I'm caged in a white prison.