Killer Instinct will be free when it launches alongside the Xbox One, but will charge players for a majority of its roster, Microsoft's Torin Rettig told Polygon in a recent interview.

The game, in development at Double Helix Games, will include a single playable character, Jago, at launch, and will require players to purchase additional characters to unlock the remainder of Killer Instinct's roster.

"Most fighting games that come out are disc based games where you get a huge cast of awesome characters, but it is a massive cast," Rettig told Polygon. "Some games have anywhere between 30, 40, even 50 characters. And in reality, most players don't play that many characters. You just only have so much time to get good at so many characters. So we wanted to take that into consideration and release the game in a way that took that into consideration and allowed players to get in and play the game at the level that they want to play it.

Editor markup for Killer Instinct E3 2013 screens. This is only visible in the story editor.

"So the way this game will work is when it releases, you'll be able to play one character for free," he added. "You'll be able to just download the client and play that character — Jago — as much as you want. And you will be able to buy other characters and other content as you see fit. So as much or as little as you want. We wanted there to be basically a wide funnel. We wanted as many players to get in and enjoy the game and experience the game as possible, and to engage in it at a level that they want to engage at."

No matter what characters they own, players will still be able to fight against the whole rostere online, which Microsoft hopes will inspire players to pick up the characters they enjoy sparring with. Rettig also said that the team at Double Helix "want to release the content is we want to release characters at a regular cadence," and will continue to add new characters to the game "as long as players are interested."

Update: A developer from Double Helix confirmed to us that there would be an equivalent to a season pass for Killer Instinct, allowing those who want the whole package to do so with one lump sum. Regardless of which option you go for, Killer Instinct will still be download-only.