Petroglyph already revealed that the Battle for Graxia team is working on a revamp of Kaos for the next playable immortal released for the MOBA. Kaos 2 will be completely redone and there's another peek at his Starship skin out as well.
But, beyond the release of Kaos, Steve Wetherill, the game's producer revealed that two new immortals are in the works for release. Battle for Graxia has been in open beta for just over a month now, and the first two releases, Ustat, and now Kaos 2 are both tests of a sort. Ustat is the full-fledged release, while "the KAOS2 rework is a test of our new art team and new pipeline". Aside from Kaos 2, who will arrive next month, there are two playable heroes already on the internal dev server and one of them will also be released in January as well.
Looks like there are still kinks the team is working out with the revamp and release schedule, but development surely continues.