Twin Nova: Collapsar Blade

Echoes drop from two different sources, and which one applies to this echo depends on its sonata family and cost.

• Open-world enemies anywhere on the map drop echoes for free, no stamina cost — this is the main way to pick up common echo bases and off-cost pieces.
• Tacet Field encounters are dedicated boss fights that cost Waveplate (the game's stamina resource) to enter, and each Tacet Field is tied to a specific sonata set — so you farm one sonata bundle at a time rather than random drops.
• The heaviest cost-4 echoes, often called Calamity echoes by the community, only drop from Tacet Field bosses — there's no open-world shortcut for the strongest cost-4 pieces.

Before spending Waveplate, confirm this echo's sonata set is actually the one your build needs — Tacet Field runs are repeatable but each run only targets one set.

Every echo carries a fixed cost of 4, 3, or 1, and that cost locks in exactly which main stat options are even possible on it.

• Cost 4 slots roll the highest-impact main stats — Crit Rate up to 22.0% or Crit DMG up to 44.0% at level 25, plus a Healing main stat option. This is the slot worth being pickiest about.
• Cost 3 slots roll elemental DMG Bonus up to 30.0% or Energy Regen up to 32.0% — match the element to the character's actual damage type or the slot is wasted.
• Cost 1 slots roll HP% up to 22.8%, flat HP up to 2280, or ATK% options, and are the cheapest slots to fill out a team's total cost.
• Total team cost is capped, so the standard 4-3-3-1-1 layout balances one big main-stat slot with cheaper filler, while some builds run 4-4-1-1-1 when two strong main stats matter more than a cost-3 slot.

If this echo doesn't sit in the cost slot your build actually needs, it's filler — check the team's target cost layout before deciding to level or Tune it further.

Substats don't appear the moment an echo drops — each of the 5 substat lines only unlocks (and can be re-rolled) by spending a Tuner on it, and every substat has 8 possible roll levels (flat ATK and flat DEF only have 4).

• Crit Rate rolls between 6.3% and 10.5% per line, Crit DMG between 12.6% and 21.0% — these are the two lines a DPS or Sub-DPS role should chase hardest.
• DPS / Sub-DPS builds: prioritize Crit Rate and Crit DMG first, then ATK% and matching skill-type DMG%, with flat ATK and Energy Regen as lower priority and HP/DEF worth nothing.
• Healer / Support builds: flip the priority entirely toward HP%, Energy Regen, and DEF%, with Crit Rate/DMG barely mattering — a support echo loaded with Crit substats is usually a wasted roll.
• Substat values come from a fixed pool that doesn't depend on the echo's rarity, so a low-rarity echo can out-roll an expensive high-rarity one if the lines land right.

Run this echo's current substats through the Echo Scorer tool on GameVika to get a role-weighted score instead of eyeballing whether a roll is worth keeping.

Since version 2.0, some echoes have a Nightmare variant — a stronger version of the base echo that behaves differently from a normal echo's passive.

• A Nightmare echo's buff activates just by being equipped in the main slot — no need to summon it or trigger anything extra to get the passive benefit, which fits fast-swap rotations well.
• The one notable exception is Impermanence Heron, which belongs to a different sonata family and doesn't follow this equip-only rule.
• If this page's echo has a Nightmare version, treat it as generally the stronger pick over the base version for the same sonata set, all else equal.

Check whether the specific echo on this page is a Nightmare variant or the base version before assuming its buff behavior — the two don't always work the same way.

Whichever echo sits in the main slot also determines the active Echo Skill a character can trigger mid-combat — separate entirely from the sonata set bonus.

• Combat in Wuthering Waves revolves around building Concerto Energy through attacks, then swapping out to fire an Outro Skill that buffs whoever swaps in next to use their Intro Skill — the quick-swap chain that defines rotations.
• An Echo Skill is triggered manually during this chain, so its best use depends on the cooldown and effect of the specific echo — some are best fired right before an Outro Skill swap, others work better as a standalone burst when nothing else is on cooldown.
• Changing which echo occupies the main slot changes both the Echo Skill available and, if it's a Nightmare echo, the passive buff — so a main-slot swap is really two decisions bundled into one.

Slot this echo's skill into the rotation window where its cooldown lines up cleanest with your swap-cancel timing, rather than firing it on cooldown regardless of context.