The Seven Deadly Sins: Demonic Beast Surtr Persona Clear Guide

To clear Demonic Beast Surtr through Floor 3 without managing stance cancels or burn debuffs in The Seven Deadly Sins, use high-burst Persona collaboration damage dealers to defeat each phase within one to two turns. Burning down Surtr's health bars immediately skips his protective buffs, damage caps, and wipe mechanics across all three floors.

Team Composition and Role Requirements

The strategy requires pairing a high-damage Persona carry with offensive support and stat amplification so attacks overcome Surtr's defense before mechanics trigger.

Slot / Role	Recommended Unit Type	Gear Set	Primary Responsibility
Main DPS	Persona Attacker (e.g., Joker, Queen)	Attack / Critical Damage	Deals primary single-target burst to eliminate phase health bars instantly.
Secondary DPS / Enabler	Sub-DPS with debuff utility	Attack / Critical Damage	Lowers enemy defense values and chips down remaining armor or side targets.
Buffer / Support	Stat amplifier and healer	HP / Defense	Increases squad attack stats and provides party survivability.
Sub Slot	Backline stat anchor	HP / Defense	Provides passive team combat stats without entering the active field.

Set your main attacker’s bracelet and ring substats to rolled Attack values between 13.5% and 15% to clear required damage gates. Equip support units with HP and Defense sets to increase total team Combat Class, which ensures your team takes the opening turn on every floor. Consume Attack or Critical Damage food before starting the battle.

Floor-by-Floor Battle Sequence

Follow this attack sequence to transition cleanly between phases and prevent Surtr from executing retaliatory strikes.

Floor 1: Card Setup and Gauge Building

Phase 1: Attack Surtr using basic skill cards to clear the phase within two turns. Save high-tier burst cards and build Ultimate Move gauges on your damage dealers.
Phase 2: Surtr activates a defense buff. Play remaining single-target attack skills to break through the shield and clear the floor while holding Ultimate Move cards in reserve.

Floor 2: Bursting Past Damage Reduction

Phase 1: Deal moderate damage on Turn 1 to reduce Surtr below half health, then defeat him on Turn 2.
Phase 2: Surtr applies damage mitigation. Lead with a defense-reducing skill, then follow immediately with your primary single-target attack cards. A critical hit clears the phase in one turn and prevents Surtr from assuming his lethal stance.

Floor 3: Mechanic Skip Sequence

Phase 1: Cast stored Ultimate Moves and high-rank cards on Turn 1 to eliminate the boss before ignite debuffs can spread.
Phase 2: Surtr enters a revive or damage-capped state. Play multi-hit, single-target attacks every turn without pausing to stall or defend.
Phase 3: Unleash all remaining Ultimate Moves and rank-three attack skills. The passive stat reduction from your Persona units allows direct damage to deplete Surtr's final health pool before his enraged state activates.

Card Sequencing Rules

Maintain strict card priority to avoid running out of offensive options on later phases:

Lead with utility: Always place defense-reducing debuffs or gauge-generating cards in your first action slot to increase the output of subsequent attacks.
Avoid passive merging: Do not skip attacks to merge cards when an active damage threshold must be met.
Recover from bad draws: If your hand lacks high-tier damage during Floor 3 Phase 2, manually merge cards to secure a guaranteed Ultimate Move for the next turn rather than using weak rank-one skills against Surtr's damage mitigation.