In a dystopian 2023, the Sentinels launched a war against the mutants, wiping out most of humanity and left only the "worst" of humanity left to rule the world. These Sentinels have been created using Mystique's DNA which gives them the ability to adapt to mutant powers and even use some. The surviving X-Men gather in a monastery in China for a last stand against the Sentinels

The sentinels powers include Superhuman strength, Superhuman durability, Superhuman agility, Flight, Energy-based weapons, Mutant gene detection, Telepathic immunity, Limited self-repair, Mutant power absorption, Shape-shifting, and Power mimicry

You’re a mutant and the sentinels spot you