Battle of the Atom
2013When the time-displaced original X-Men refuse to return to their era, a team of future X-Men arrives to force them back — but their motives aren't what they seem. Multiple factions of present and future X-Men clash over the timeline, free will, and the right to choose your own destiny. A sprawling anniversary crossover that pits X-Men against X-Men across three generations.
8 core issues, 0 optional tie-ins/crossovers

Part 1 — A near-death experience with the young X-Men prompts the future X-Men to intervene

Part 2 — The future X-Men arrive and demand the originals return to their time

Part 3 — Young Cyclops and Jean flee to Cyclops's team; the future X-Men pursue

Part 4 — A second team of future X-Men arrives, revealing the first group are impostors

Part 5 — The true future X-Men join the fight; battle lines are redrawn

Part 6 — All-out war between present and future X-Men factions

Part 7 — The impostor future X-Men's true plan is revealed

Part 8 — The original five decide to stay in the present; the future X-Men are defeated