"Hellfire Gala" was initially a 12-part X-Men comic book storyline published by Marvel Comics in June 2021. It is the first storyline featured in the "Reign of X" relaunch after the "X of Swords" storyline. From Wikipedia
The May 30 update introduces Ultron as a playable Strategist, a revamped Arakko map, significant balance changes, new Team-Up abilities, and experimental features.
