This Lightning Returns: Final Fantasy XIII video titled Lightning Collection 2013 in Luxerion shows many different kinds of garb Lightning can wear. Changing into a different costume alters Lightning’s stats and the abilities she can use in battle. It’s kind of light Final Fantasy X-2’s dress change system, but with only one character in battle.
The first outfit is Equilibrium, Lightning’s standard look in Lightning Returns. Garb can be further customized by changing colors for different pieces of the outfit. Keep your eyes peeled for the Cloud costume, the Miqo’te outfit from Final Fantasy XIV, and Lightning’s old costumes from the other two Final Fantasy XIII games.