Infinite is endless waves. The run ends when your team wipes. You still pick Easy, Medium, Hard, or Nightmare, and those health multipliers match Story.
Boss interval
| Difficulty | Boss every |
|---|---|
| Easy | 10 waves |
| Medium | 8 waves |
| Hard | 6 waves |
| Nightmare | 5 waves |
Infinite bosses started dropping materials on October 2. Before that patch they did not, which is why older farming advice skipped this mode. Waves also scale further in as the October 1 note put it, and extra players make enemies tougher.
A most-waves leaderboard was added October 1. Level milestones are reported up to 500 in pre-release footage. That cap is a footage report, not a number printed on a later patch note.
How to last longer
Funnel packs so that only the two attackers who are allowed to hit you can reach you. Do not spend ultimates on rubble. Bring Luffy + Shanks if the later waves are a health problem. A raw damage pair falls off when enemy health outscales your clear speed. Bosses still do not flinch, so learn the pattern instead of trading hits.
Use Infinite when the Story act that drops your material is already trivial, or when you want leaderboard depth. Use Story when you need one act's specific list and a known payout.