Xbox One owners who stream Rise of the Tomb Raider via the system's Twitch integration can let their viewers decide how the game progresses in certain ways, making it easier, more difficult or just plain weirder, Microsoft, Crystal Dynamics and Twitch announced today. Viewers watching someone else stream the game can also benefit, receiving in-game gifts by watching select in-game events.

Rise of the Tomb Raider's Twitch integration can be experienced by players when streaming the game's Expedition Mode. At certain points in that mode, viewers can vote via Twitch chat on one of two Expedition Cards. Those cards will then grant special modifiers, like making enemies more difficult or engaging "big head mode." According to Twitch's official FAQ, the game features "a curated set of 64 cards have been arranged into 186 pairs for viewers to vote on."

Viewers have a reason to tune in: If they watch certain moments in Expedition Mode, like side missions, challenge tombs and special achievements, they can earn in-game currency.

While similar types of Twitch integration have been attempted before, through efforts like Daylight and Dead Nation: Apocalypse Edition, it's still uncommon to see it in such high profile games like the new Tomb Raider. More details on Rise of the Tomb Raider's Twitch integration are available on Twitch's website.

For more on Rise of the Tomb Raider, read Polygon's review.