Should you want to skip the grind, there are packs available to get handfuls of characters at a discounted rate compared to buying separately, but I can't recommend doing such a thing. (thexboxhub.com)
This seems to suggest that Paramount is sticking with the small handful of characters who actually worked in the original film — one of whom has plastic lips that don't move — and vetoing the likes of Sienna Miller, Marlon Wayans, Dennis Quaid, and even Joseph Gordon - Levitt who was clearly set up as the villain Cobra Commander in a potential sequel. (collider.com)
All of the PS3 version's downloadable content is included here, but that amounts to a small handful of character skins and Challenge of Exile mode; a totally unremarkable set of assessments that is as lightweight and disposable as you'd expect from an add - on that arrived before DLC was really a thing. (gamestm.co.uk)