Zeta
Zeta is a 5★ Vanguard-class Partner in Chaos Zero Nightmare. Equipped on a Combatant, Zeta raises DEF by +16–24% (Always active) and DEF-based DMG by +15–31% (with an Instinct card). Zeta's EGO skill, Undertaking the Mission, can be used for 2 cost. Rewritten in plain terms from in-game data — not a copy of the original wording.
Partner Passive
Deadly Poison
What this partner does when equipped, explained buff-by-buff (values shown as a low→high investment range).
| Buff | Amount | Condition |
|---|---|---|
| DEF | +16–24% | Always active |
| DEF-based DMG | +15–31% | with an Instinct card |
| DEF-based DMG | +25–50% | with a Celestial card |
| Shield | +25–50% | with a Celestial card |
Rewritten in plain terms from in-game data — not a copy of the original wording.
Level-by-level upgrade table
Official in-game data across all 5 investment tiers (not just the low–high range).
| Buff | Tier 1 | Tier 2 | Tier 3 | Tier 4 | Tier 5 |
|---|---|---|---|---|---|
| DEF · Main stat boost | +16% | +18% | +20% | +22% | +24% |
| DEF-based DMG | +15% | +19% | +23% | +27% | +31% |
| DEF-based DMG & Shield (Celestial card) | +25% | +32% | +38% | +44% | +50% |
Rewritten in plain terms from in-game data — not a copy of the original wording.
EGO Skill
A special skill this partner can activate by paying the cost below.
200% Defense-Based Damage. Draws 1 highest-cost card.
Is Zeta Worth Investing In?
Zeta is a 5★ partner whose passive raises DEF by +16–24% across 5 official investment tiers — a solid pick whenever your team needs that stat.
Which Combatants Does Zeta Work Best With?
Zeta is a Vanguard-class partner. Its main effect grants a DEF bonus, so it fits any Combatant whose damage or survivability scales with DEF, not just one fixed unit.
What Does Zeta's EGO Skill Do?
Zeta's EGO skill, Undertaking the Mission, costs 2 and does the following: 200% Defense-Based Damage. Draws 1 highest-cost card.
