Who would win in a fight between these two power house heres some back ground infomation
Itachi... and his Sharingen
here is an except from narutokun...
"...But the most terrifying aspect of Itachi is his infamous Mangekyou Sharingan, the deadliest form of them all. The Mangekyou casts off a Genjutsu (Tsukiyomi) that is absolutely impossible to dispel, a technique that can completely submerge the victim in to a parallel world where time for he or she passes much slower for in an instant in the real world, 24 hours passes in this dimension, The World of the Grasping Moon, as Itachi calls it. What really makes this technique deadly however, is the fact that the user can do anything to his victim that he wants, from making him relive moments of his life, to torturing him for 72 hours at a time with the blink of an eye..."
on a side note... here is another excerpt from narutokun about the sharingan
"However, despite its immense destructive power, the Mangekyou Sharingan is a double edged sword. Hence, the Sharingan 'causes a terrible strain on the user's eyes and eventualy deteriorate his eyesight."
Aizen... and his Kyouka Suigetsu (Mirror Flower, Water Moon)
um do i need to say anything about Aizen?? COMPLETE HYPNOSIS
basically as long as someone has seen his swords they are under his complete hynosis.
Um I have to say I really can't imagine who would win... because both of them possess almost the same kiind of power...they can both create illusions...well give me your thoughts.