Combat & Reaction System Guide
Complete Arknights: Endfield combat guide: resilience bar mechanics, four-layer Vulnerability stacks, and skill pre-charge techniques.
1. The Resilience Bar
Every enemy has a resilience bar. Until it breaks, Crush damage is heavily resisted. Breaking it opens a damage window — this is where burst rotations pay off. Regeneration timers vary by enemy, so apply control (Freeze, Entangle) to pause the bar.
2. Four-Layer Vulnerability
Vulnerability stacks multiplicatively up to four layers. Apply it via Nature or Pulse sources before detonating your element reaction. Four layers roughly double the damage of your shatter/Crush hit. Coordinate casters and strikers so the detonation lands inside the broken window.
3. Skill Pre-Charge Technique
Build Endskill charge through basic attacks and Pulse batteries before the break window. When the bar breaks, immediately fire your Endskill so the full multiplier lands inside the window. This is the core optimization for Umbral Monument deep floors — see the Boss guide.
Frequently Asked Questions
What does the resilience bar do?
It gates break damage. While it is not broken, the enemy resists Crush. Breaking it opens a window where Crush and Vulnerability-stacked hits deal massively increased damage.
How do I stack four layers of Vulnerability?
Layer Nature or Pulse applications in sequence, then refresh before expiry. Coordinate a Caster to apply and a Striker to detonate inside the window.
What is skill pre-charge?
Building charge from basic attacks and Pulse batteries before the break window so your Endskill lands immediately when the bar breaks, maximizing the burst window.