Tattoos
The tattoos that you can get from Marvin the tattooist in Arkham can improve your stats, and give you various affects, but you can only get ONE during the entire career of you character; if you get the low-level Skull tattoo at level 10, that's it. So if you want to get the high level Flying Dragon tattoo, you'll have to wait for a lot of levels without having any tattoo.
