Chaos Zero Nightmare Skill Damage Formula Breakdown: How modifiers and combos stack

Chaos Zero Nightmare’s damage is mostly multiplicative layers on top of Final ATK/DEF, with card multipliers and buffs/debuffs stacked into a single “Final Card Multiplier” before being applied to your stats. Understanding which effects are additive vs multiplicative tells you exactly why some combos explode and others barely move the needle.​​

Step 1: how Final ATK / DEF are calculated

Outgoing damage always starts from your Final ATK / Final DEF, which already include gear, partner, and affection.

• Final ATK formula
  • \text{Final ATK} = (\text{Base ATK} \times (1 + \text{ATK% increase}) + \text{Partner ATK} + \text{gear flat} + \text{affection flat}) \times (1 + \text{Partner ATK%} + \text{equipment ATK%}) + \text{equipment flat}.​
  • All flat ATK sources add together, then get multiplied by %ATK bonuses, then you add flat gear on top.​
• Final DEF and HP are calculated in the same structure (base → % → partner/gear → flat), and DEF can be part of damage if a card is DEF‑scaling.​

Takeaway: ATK% and flat ATK scale everything; partner stats and affection are multiplicative with base stats in the first term and with equipment % in the second.​

Step 2: card multipliers and how they stack

Each attack card has a base multiplier (e.g., 280%), which gets modified in multiple layers before being applied to your ATK/DEF.

• Final Card Multiplier (condensed)
  • Prydwen’s formula:
    • $\text{Final Card Mult}=[(\text{Base Mult}+\text{Potential add})\times (1+\text{Potential mult})]\times (\text{generic mult})+\text{generic additive}$Final Card Mult=[(Base Mult+Potential add)×(1+Potential mult)]×(generic mult)+generic additive,
    • then multiplied by element and debuff layers like:
      • $(1+\text{element advantage})$(1+element advantage)
      • $(1+\text{Vulnerable mult})$(1+Vulnerable mult)
      • $(1-\text{enemy damage reductions})$(1−enemy damage reductions)
      • $(1-\text{Weakness mult})$(1−Weakness mult).​
• Example: Anchor Shot scaling
  • Game examples show Anchor Shot base 280% + 10% Potential = 308% before other modifiers.​
  • Skills like Energy Charge (+30% attack card damage) and Pull Up (+70%) apply as additive damage buffs to the card, i.e., a combined +100% to that card’s damage layer.​
• Additive vs multiplicative buffs
  • Testing Morale shows +20% damage per stack as a multiplicative layer applied late, not added into the card multiplier pool.​
  • Vulnerable has been tested as a 1.5× multiplicative buff: 449% base rising to 741% damage with one stack, which matches $449\times 1.5$449×1.5.​
  • Reddit clarifications: multiple multiplicative buffs (like several “×X% damage” effects) are added together into a single multiplier, then that one multiplier is applied; they don’t individually chain multiply each other.​

So: card‑specific buffs (like “this card deals +30%”) often stack additively on the card layer, while Morale/Vulnerable/Weaken are larger multipliers closer to the end of the formula.​​

Step 3: the core damage formulas (ATK vs DEF‑scaling)

Once you have Final ATK and the Final Card Multiplier, the game computes damage with slightly different formulas depending on whether a card is ATK‑based or DEF‑based.

• ATK‑based damage
  • \text{Final Damage} = \text{Final Card Mult} \times \text{Final ATK} \times 0.35 \times (1 + \text{elemental DMG%}) \times (1 + \text{mechanic DMG%}) \times (\text{enemy DEF multiplier}) \times (1 + \text{Crit DMG}).​
  • The 0.35 is a game‑wide scaling constant; people asking “does 100% card = 35% ATK?” are basically seeing this constant in action.​
• DEF‑based damage
  • \text{Final Damage} = \text{Final Card Mult} \times [(\text{Final ATK} \times 0.3) + (\text{Final DEF} \times 2.1)] \times 0.35 \times (1 + \text{elemental DMG%}) \times (1 + \text{mechanic DMG%}) \times (\text{enemy DEF multiplier}) \times (1 + \text{Crit DMG}).​
  • DEF builds gain from both ATK and DEF; every extra point of DEF gets multiplied by 2.1 and passed through the same global modifiers.​
• Enemy defense & mitigation
  • $\text{enemy DEF multiplier}$enemy DEF multiplier compresses or expands final damage based on enemy DEF and defense‑down effects; Vulnerable and similar debuffs effectively improve this term.​​

Key point: most “+X% damage” mechanics are multiplying the final damage after the 0.35 constant and DEF term, so they scale harder the more ATK/DEF you stack up front.​​

Step 4: how common buffs and debuffs stack in practice

Several key buffs/debuffs have been lab‑tested so you can plan combos precisely.

• Morale (damage up)
  • Each Morale stack gives +20% damage as a multiplicative layer added late, not as card power.​
  • Example from testing: one stack changes damage from 248 to ~298–300, consistent with a 1.2× multiplier applied after earlier terms.​
• Fortitude (damage taken down)
  • Each stack reduces damage by 20% additively with itself, e.g., 1 stack = 20% less, 2 stacks = 40% less, etc.​
  • This stacks linearly but multiplies against your final damage, making Fortitude extremely efficient for survival.​
• Weaken (damage dealt down)
  • Tested as a 25% damage loss per stack; removing a Weaken stack jumped damage from 114% to 152%, which fits $152\times 0.75\approx 114$152×0.75≈114.​
  • Effectively a multiplicative reduction (×0.75 per stack) applied late in the chain, similar to Morale but in reverse.​
• Vulnerable (damage taken up)
  • One stack increases incoming damage by about 50%; Anchor Shot testing showed 449% → 741%, which is exactly ×1.5.​
  • Multiple stacks appear additive in the same layer (e.g., two stacks ≈ ×2.0 overall), rather than exponentiating.​​
• Talent / mechanic DMG% boosts (e.g., Agony, DoT, element)
  • These sit in the (1 + elemental DMG%) and (1 + mechanic DMG%) slots, multiplying the ATK/DEF‑scaled value.​​
  • For Agony specifically: every 100 ATK ≈ 7 more Agony damage, every 10% Void ≈ 9% more Agony, every 10% DoT ≈ 8% more, these are effectively linear multipliers on top of the base ATK‑driven dot formula.​​

High damage turns happen when you stack: card buffs → Morale / mechanic DMG → Vulnerable → crit, all multiplying each other after your big ATK/DEF foundation.​​

Practical building and combo rules

Using the formula, you can simplify optimising into a few rules:

• Prioritise ATK/DEF + card multipliers first
  • Because everything multiplies off Final ATK/DEF and card multipliers, raising those gives the biggest baseline increase.​
• Stack one strong “late” multiplier at a time
  • Morale, Vulnerable, element DMG, mechanic DMG% are all late multipliers; having one or two high stacks of them is better than several small, overlapping ones that share the same layer.​​
• Avoid over‑investing in additive card buffs alone
  • Skills like Energy Charge (+30%) and Pull Up (+70%) on Anchor Shot are additive on the card, so they’re great but don’t snowball as hard as late multipliers like Vulnerable.​
• For DEF‑scalers, push DEF hard and still care about ATK
  • Because DEF cards compute $(0.3\times \text{ATK}+2.1\times \text{DEF})$(0.3×ATK+2.1×DEF), DEF is king, but ATK still contributes and also boosts any dot mechanics attached.​​
• Remember Weaken / Fortitude as “formula levers”
  • Weaken and Fortitude are literally editing the final multiplier; removing Weaken or adding Fortitude can swing damage by 40–60%+ with just a couple of stacks.​

If you think in these layers, Final ATK/DEF → card multiplier → buff/debuff multipliers → crit, Chaos Zero Nightmare’s damage stops feeling mysterious, and you can build combos that hit the exact breakpoints you want instead of just stacking random “+X% damage” lines.