Quick take: use a room code when you already know who you want to play with, use public matchmaking when you just want a fast room, and host only when you want control over the target run. Co-op works best when the host sets a clear goal and joiners bring a build that already clears similar content.

Quick Answer

Co-op supports up to four players and is best used for bosses, shrine floors, and repeated reward runs where help saves time. Most room decisions come down to room codes, public matching, and a clear host goal. The clean rule is simple: host when you need control, join when you just need clears, and keep the room goal obvious.

What Co-op Is Best For

Harder bosses

If solo boss attempts are wasting time or revives, co-op is the clean fallback.

Shrine-style challenge floors

Co-op matters more when a fight demands safer execution than when you are just overclearing easy story content.

Repeated farm targets

Once everyone in the room wants the same reward, co-op becomes an efficiency tool instead of a social detour.

Room Code vs Matchmaking

Option When to use it
Room code Best when you are inviting friends, retrying one exact piece of content, or want the room to stay on one farm target.
Public matchmaking Best when you want a quick fill and do not care who joins as long as the room clears.
Friend support and stamps Useful for basic coordination, but not a substitute for a clear host plan or a prepared build.

When to Host and When to Join

Host if you need control

Host when the content target matters, when you want to repeat one boss or shrine floor, or when you need to invite a specific group through a room code.

Join if you need speed

Join when your only real goal is faster clears. This is the lower-friction option when you do not need to manage the room yourself.

Switch if the room goal changes

If you want to move from quick public clears into planned farming, stop joining random rooms and host your own code room instead.

Simple Host Checklist

  1. Pick one target before opening the room.
  2. Use a room code if you want the same people or the same plan across repeats.
  3. Bring a build that already clears the content comfortably.
  4. If runs keep failing, simplify the reward plan and build setup first.

Simple Joiner Checklist

  1. Join rooms that match content you already clear or nearly clear.
  2. Assume the room wants stable clears unless the host says otherwise.
  3. Bring a tested setup into farm rooms.
  4. If the room is wiping, simplify your setup before trying a higher-risk carry plan.

What Busy Rooms Change About the Advice

Co-op can turn messy when four players fill the screen with effects, movement, and boss pressure. That makes three habits more important than they might look on paper:

  • Clear visual telegraphs beat flashy clutter.
  • Low-maintenance damage beats fragile “perfect run” rotations.
  • Team-first pacing beats one player forcing the room around a risky setup.

Current Multiplayer Events

The following raid events are currently active or recently available in co-op. Use these guides for unlock conditions, team composition, attack patterns, and clear rewards.

  • Killer Machine Army Raid Guide — Active multiplayer raid with machine-family enemies. Check for team recommendations and attack pattern breakdowns.
  • Ryuuou Army Raid Guide — Previous multiplayer raid guide. Use for historical context or if the event returns.

FAQ

How many players does co-op support?

Co-op supports up to four players in one room.

Should I use room codes or public matchmaking?

Use room codes when you want control or known teammates. Use public matching when you want quick fills and do not need the room to stay private.

Is it better to host or join?

Host when the target run matters and join when speed matters more. The better option depends on whether control or convenience is the real bottleneck.

Should I use co-op to test new builds?

Usually no. Shared rooms work better when everyone brings a build that already clears similar content.