: Hostile players can forcibly enter the worlds of those currently engaged in co-op play. Invasions are typically 2v1 or 3v1, as invaders must contend with the host and their allies.

: For balanced competition, players can use the Duelist's Furled Finger to leave a red sign for 1v1 fights. Dedicated Coliseums also offer structured modes like Team Battles and Free-for-Alls.

: Used to place a gold summon sign to help others.