Microsoft is offering selected Xbox fans free access to Killer Instinct's complete character roster.

Emails detailing the promotion are alleged to have been sent to Xbox users by Microsoft earlier today, thanking them for "dedication to Xbox".

"You're a fan of ours and we're a fan of yours," reads the email. "Thank you for your dedication to Xbox. We want to show you our appreciation, so we're giving you: Killer Instinct. We've unlocked all characters so you can hit the ground running.

"Watch your inbox on 22 November for instructions on how to claim your free gift."

The message continued: "We wouldn't be here without you, and we know you'll do amazing things on Xbox One. Thank you from Xbox Live."

The selection process surrounding the promotion still seems vague, although multiple NeoGAF users claim to have received the email.

Killer Instinct launches as a free-to-play title alongside Xbox One on November 22.