What are your thoughts regarding Achilles?

I find Achilles a most fascinating character. His mere presence on the battlefield changes the fighting prowness of the Greeks to an almost unbeatable level. Yet without their 'hero' they really struggle. Achilles is also reavy interesting to read about it. He possesses it would seem such individuality and at times selfishness? As many of his kins men are dying largely it could be argued to Achilles absence from the battlefield - Achilles seems quite content to sulk with some of the elite troops of the Greeks and forbid them from fighting as well. Yet when Achilles returns to the battlefield in a rage he is a killing machine and cannot be stopped in his fury. Even the 'second' best fighter and 'hero' Hector runs away from Achilles and resists very feebly to the killing machine Achilles. The self absorbed individualistic streak in Achilles and his 'heroic' make him stand out amongst his fellow Greeks.