The first game, Marvel Super Hero Squad, is a casual MMO aimed at younger folk.
The second, Marvel Universe, is in development for PC and consoles. Gazillion will develop and publish the game, with more details to arrive in the coming months.
City of Heroes developer Cryptic Studios previously worked on an MMO titled Marvel Universe Online, though it was later cancelled due to World of Warcraft-related fears.
According to today's announcement, Gazillion has been "operating in stealth mode" under the name NR2B Research. The publisher has four wholly-owned MMO development studios: Amazing Society (Super Hero Squad), Gargantuan (Marvel Universe), NetDevil (LEGO Universe, Jumpgate Evolution), and id co-founder John Romero's Slipgate studio, which is working on an original MMO.