In addition to added support of the Oculus Rift virtual realty headset and Razer Hydra motion controls, Surgeon Simulator 2013, Bossa Studios' surgical simulation game, will let players swap characters from Valve's Team Fortress 2 into the surgeon and patient roles.

The Team Fortress Medic and the Heavy will be available as the operator and operated-on, respectively, with the game's next free update, which is slated to launch over the weekend.

"It's absolutely hilarious," Bossa Studios co-founder Imre Jele told Polygon. "Working with Valve has been amazing because they are flexible and cool guys. We said, 'It would be great if we could have those two characters in Surgeon,' and they said, 'That's fantastic, let's do that.'"

Jele said the addition was inspired by feedback from players. He said he has seen "a ton" of fanart of the Team Fortress 2 Medic operating Surgeon Simulator-style, as well as fan-made videos dubbing the Medic's voice over an operation in Bossa's game. He added that the collaboration with Valve also extends to the characters' voice acting, bringing the full experience of Team Fortress 2's crazy doctor into their game.

"If you don't ask, you don't get, and we originally totally expected [Valve] to say no," Jele said "They immediatley said this was a fantastic idea and collaborated with us.

"We'd like to continue collaborating with Valve, since [both Team Fortress 2 and Surgeon Simulator 2013] match each other in mood and sense of humor," he added.

"The game is already pretty weird. But now you put that helmet on and it's just so real."

Jele said Surgeon has become a social game: although it lacks any true networking features, it has brought together a community that shares its experiences and fan-made creations.

"What's exciting for us is that Surgeon Simulator is now a truly social game," he said. "The fact is, people want to talk about it and want to share their experiences. This is what makes a game social, despite having no multiplayer in it. The number of unique fan videos and playthroughs we find on YouTube is amazing."

Of the game's recent virtual reality integration, Jele said Bossa Studios wanted to work with the Oculus Rift from the moment they backed the hardware on Kickstarter. After receiving their dev kit and toying around it with, Jele said the team knew it would become a hot topic — and they needed to join the game fast.

"Being in a company of nerds, you have this drive to try all the new things," he said. "Obviously everyone was going to jump on it and we wanted to try something ourselves. It made sense to add it to Surgeon Simulator."

Adding the Razer Hydra's motion controls resulted in a "brilliant setup," he added.

"Adding the Hydra was the cream on top because we were already on a roll [with the Oculus Rift], and we created this really cool thing where we could use the coolest and latest gadgets and put it all in our game," he said. "Both tools complement Surgeon Simulator really well.

"The game is already pretty weird. But now you put that helmet on and it's just so real."