Ezio’s outfit is a reward on Uplay, that you can unlock for 30U. You can only get this one with special edition of AC III. You are awarded with Altair’s outfit if you get 100% synchronization of all story missions. You will get Captain Kidd’s outfit after you complete all PegLeg missions (after you finish ‘Oak Island’, you will be able to prance around wearing Kidd’s robes). You can unlock Kanien’keha:ka outfit by collecting all the feathers. This outfit unlocks when you complete sequence 8. You will get Achilles Outfit when you complete all Homestead missions.
You will get assassin’s outfit after completing sequence 5.
Here are all Assassin’s Creed III outfits: There are outfits that you will only unlock after completing some quests, sequences or similar. As usual there are several different outfits in AC games.
