Deck combat is a continuous, real-time battle mode in which squad leaders draw and play monster and support cards while teammates protect them and fight normally.
A squad may voluntarily activate a full deck against ordinary phase-one monsters by removing it from inventory during combat. If an opposing squad or intelligent enemy has enough cards to form a deck, activation becomes mandatory.
Combat begins when an aggroed monster actively hunts the squad and ends when enemies die, become neutral, or a party flees. Overlapping mobs count as one session, so defeated totems may remain unavailable throughout a large target-rich area.
The mode is not turn based. Timing, preparation, squad synergy, hidden enemy cards, and the squad leader's temporary loss of ordinary tools all operate simultaneously.
Summoned monsters and crawler fighters battling in real time around a leader manipulating a four-card hand.
Deck combat is the eighth floor's central phase-two system and a compulsory layer in any battle between equipped squads.