It is believed that Master Chief will soon be coming to Rainbow Six: Siege. This information has not yet been confirmed by Ubisoft but in a leaked clip we can see the new Elite Skin for Sledge, which shows the UNSC Spartan in all his glory.
The leak was first posted by Twitter user Klobrielle, who is usually well-known for spotting information early. Master Chief has made crossover appearances before, so it does seem possible for him to step into Rainbow Six: Siege.
<social>https://twitter.com/klobrille/status/1691154122660077568</social>
If this crossover does turn out to be real, it'll likely be an incredibly popular one. Would you pick up the Master Chief Sledge skin?