Bongo Bongo

Invisible (This creature cannot be blocked by
creatures with a toughness less than it's own.)

"Not much is known about Bongo Bongo but this; it
is a vastly evil spirit, originating from Kakariko's
infamous Shadow Temple. It has been sealed
and escaped twice now, and the seal is weakening
once more. Should the Sheikah fail to defeat it
again, the entire Kingdom must prepare for
disaster." -L.B. Terrus, Hylian Historian