Its a monster made out of chakra... just like in bleach... when kenpachi removes his eyepatch, or ichigo goes resolve form, remember? Its sasukes hate and anger against danzou shown in real form, how big it is.
yes but look at its head.. it seems as if it has horns too.. its faint but if u look more closely.. I think the monster has horns too... similar to the one 8-tails had.. but not sure as yet
maybe this is it "the eye of the moon" no ideacheck this out, that thing behind itachi is unique for uchihas, its prolly the thing behind sasukemaybe its the sharingans true purporse, i dont remember who but somebody said that controling the kyubi isnt all the sharingan can do and that there is even more?!
but most likely its just what "Namikaze Naruto" said xd xd
That thing just represents the power of his sharingan I think. The empty sockets were to hint that this is where Itachi planned to fill in Sasukes eyes... As pictured on the page where Madara has the same thingie behind him but with 4 eyes in it (Izunas).
