There are 4 suits you can get from gameplay, but in order to obtain every piece, you'll have to play through th game a minimum of 3 times. Don't worry, though, your second and third playthroughs will greatly sped up if you collect the pieces for the Blackest Night suit on your first go. The other three suits, however, can be collected alone the way, but the belts for each will only be given depending on which of the game's main bosses you defeat last. So, while you can collect everything besides these three pieces on any of your playthroughs, you can wait til your third to get them. The New 52 suit belt comes if you save Penguin as your last boss the Red Son suit belt comes from saving Joker for last, and the One Million suit belt will be had if Black Mask is saved for last. Whichever order you decide, remember to always do a different boss last each time. Check my other guides for more details.