Killer Instinct gets infinite Survival Mode at launch, Arcade mode after Season 1 characters
"Our Arcade mode is going to come out when we've done the eight characters," Fornace [Daniel Fornace, MS Studios Designer] said. "So it's not going to be at launch, at launch we're going to have six - Orchid's the last - and then we'll have two more following up post-launch."
"So once the last character comes out then we'll have Arcade," Fornace continued, "but in the meantime we have Survival. And Survival is like our endless mode.
"The way it works is you pick a difficulty and you go in, and you're basically playing a long chain, and after each match you regenerate health, but as you go on you generate less and less, and even if you do beginner difficulty, as you get to the higher numbers the CPU does start getting tougher, so you'll still hit a limit. You set your difficulty to where you're at - so if you set it to Champion it'll start hard and get even worse."
Source: Xbox Official Magazine
Before you ask, all characters will be out by "February or March" last we heard:
Creative director Ken Lobb guesses "February or March" is when the full roster of eight characters will be availablehttp://www.ign.com/articles/2013/08/20/gamescom-killer-instinct-season-2-in-2014-launch-explained