TMNT: Mutants in Manattan - Stealth Master Trophy ( Signore Del Silenzio Trofeo)
Includes No Damage.
The best stage to do this in is Bebops stage the residential area, which is the first stage of the game. The other turtles can be spotted and you can still obtain this trophy if just you are not spotted at all. But the best strategy is for them to not get spotted because if they do they can lead the enemy back to you. You will want to stay on the rooftops to avoid walking around on the ground and having enemies randomly pop out of the sewers right in front of you. You will want to use the Wait communication so that the other turtles wont run off on their own getting spotted by enemies. At the end of every mission when it showing you the rank you got , before that screen goes away quickly make your way to the rooftops since the enemies that are outside of the missions wont spawn in until the stat screen is gone. Try as hard as possible to only get kills when inside of a mission to prevent getting seen by the enemies, so once a mission is over find a secure spot on a roof and make sure the other turtles follow you up their as well and wait for the next mission to appear. Also try and always stay in turtle vision when traveling around so that you can see the yellow glow of the enemies in your vicinity so that you can adjust your course and make your way around them without being spotted.
I wouldn't advise it but if your caught in a situation where you have to kill an enemy outside of a mission to get by you can kill them with a take down. Just be sure that you do the take down properly, because if you fail the enemy will spot you.
( Thanks ps3trophies)