Update: Looks like the DLC won't make it today, the PlayStation Twitter account says. Drinkbox Studios will announce the new launch date later.
Guacamelee is playing dress-up with some new costume DLC tomorrow (June 5 in Europe) but these garbs aren't strictly for show: each outfit employs a type of risk-versus-reward modifier changing Juan and Tostada's traits in the game.
For example, the Pollo Luchador get-up is a bright yellow chicken suit that allows you to replenish health over time, but at the cost of slower stamina regeneration. A skeleton costume grants infinite stamina for super moves, but removes all health packs from the entire game. The third outfit of the bunch decreases throw damage but increases striking damage.
All three outfits will be sold together starting tomorrow for $1.99. The DLC will be accompanied by a patch, which will allow players to switch characters at checkpoints - right now, the PS Vita version of Guacamelee only lets you play as Juan and playing as Tostada alone on PS3 requires a convoluted process that will be moot when the PlayStation Store updates tomorrow.
Sony PlayStation 3 (late 2012)