Destroy a Vault Index Luck Guide
Hit every five-unique breakpoint, understand the 62.5% ceiling, and spend Cash without starving Damage.
Index Luck is Destroy a Vault’s quiet compounding engine. Every five unique robots you unlock grants an Index Luck boost, and completing all 76 robots totals 62.5% Index Luck. That passive stack improves roll quality and mutation frequency over time — so collection is not vanity. This guide covers the math, milestones, buy-vs-skip rules, and how Index Luck pairs with Robot Luck, fusion, and Bosses-era DPS needs. Start from the Robots & Index Hub for the wider collection overview.
The core math
- Unique robots tracked in the Index: about 76
- Luck grant cadence: +Index Luck every 5 uniques
- Full collection ceiling: 62.5% Index Luck
- Index credit persists even if a better unit replaces that robot on your active board
You do not need to field every unique. You need to own them. Deploy the highest effective DPS lineup for Gold; chase uniques for luck.
Milestone roadmap (every five)
Think in breakpoints: 5, 10, 15, 20… up through the full 76. Each tick makes the podium a little kinder. Practical pacing:
| Uniques owned | Focus |
|---|---|
| 0–15 | Buy almost every cheap unique while filling slots |
| 15–35 | Skip expensive Commons; still grab cheap new entries |
| 35–55 | Mix Index shopping with mutated power buys |
| 55–76 | Finish gaps with surplus Cash; protect Damage/Battery first |
During live Bosses pressure, slide toward the stricter rows earlier — clear speed funds the rest of the Index (Bosses).
Buy vs skip for luck
Buy for Index when:
- The robot is a new unique
- The Cash cost will not delay your next Robot Damage or Battery purchase
- Slots are already filled with acceptable DPS
Skip even if unique when:
- The price would leave you unable to clear the current vault
- You are saving a Cash buffer for an island gate (Islands)
- A mutated high-DPS offer is available for similar Cash and your board is weak
Skip duplicates when:
- They are low-value Commons already indexed
- You are not banking that type for fusion
Bank duplicates when:
- Island two fusion is unlocked
- The type is A/S-tier on the Tier List / Best Robots
- You are one or two copies from a four-of-a-kind
Fusion consumes four non-fused copies into a stronger unit that cannot fuse again (Robot Fusion). Index credit for the type normally remains once unlocked.
Index Luck vs Robot Luck vs mutations
Index Luck is the collection passive. Robot Luck is the board upgrade you buy with Cash. Together they raise the odds of rare and mutated podium results. Mutations multiply DPS on individual robots and can be forced with Gem-bought Mutation Cores (Mutations).
Efficient loop:
- Raise Damage/Battery so vaults print Gold (Upgrades, Economy).
- Smelt into Cash.
- Buy cheap uniques for the next five-unique tick.
- Buy Robot Luck with surplus.
- Core your carry when Gems (including UPDATE) allow.
- Return to Index hunting with better luck and a richer wallet.
Collectors who ignore DPS finish the Index slower because they earn Cash slower.
Funding Index with codes and offline Gold
Redeem RELEASE, UPDATE, and 100K early — codes are not case-sensitive. Steps: How to Redeem, table: Codes. Use Cash codes for Damage and occasional unique buys; use Gem codes for cores that accelerate clears so you can afford more uniques later.
Before long AFK, park your best DPS board so offline Gold funds the next Index shopping trip (Offline Earnings).
Full Index = 62.5% — why finish
The ceiling matters because late rolls decide whether you see Mythic / mutated carries or endless Commons. Players who stall at “good enough” Index often hit a rarity wall exactly when Bosses-era vaults demand more DPS. Finishing the 76 is a mid-to-late project, not a day-one chore — but every five-unique tick along the way is free power.
Session templates for Index progress
Power session: Smelt → Damage/Battery → only buy uniques that are cheap → mutate carry.
Collection session: After clears feel easy, spend a Cash surplus circling the podium for missing uniques; skip expensive junk.
Fusion + Index session: Bank duplicates of valued types while still picking up missing uniques that appear cheaply.
Mistakes that waste Index potential
- Buying every Common forever and never upgrading Damage
- Treating Index Luck as optional endgame fluff
- Spending all Gems before you have a keeper worth mutating
- Ignoring five-unique breakpoints so you never notice progress
- Going broke on a unique right before an island unlock
Related pages
- Robots & Index Hub — collection overview
- Tier List and Best Robots — what to field while you collect
- Upgrades — boards that fund Index shopping
- Getting Started — first uniques
- Updates — roster additions after patches
Chase breakpoints, protect clear speed, and let 62.5% Index Luck turn Destroy a Vault’s podium from a lottery into a pipeline.
Frequently Asked Questions
Quick answers to the most common Destroy a Vault questions.
How does Index Luck work in Destroy a Vault?
Every five unique robots grants an Index Luck boost. Unlocking all 76 robots totals 62.5% Index Luck for better rolls and mutation odds.
Should I buy a new unique or Robot Damage first?
Buy Damage (and Battery) when clears are slow. Buy new uniques when they are cheap enough that they will not delay those power upgrades.
Do I need to keep every unique on my army board?
No. Index tracks ownership. Field the highest effective DPS lineup and keep uniques for luck credit even if they leave the active slots.
When should I skip a unique offer?
Skip if the Cash cost would stall vault clears, empty your island unlock buffer, or block a mutated carry that your board desperately needs.
How do fusion and Index Luck interact?
Fusion needs four identical non-fused copies after island two. Index credit for a type normally remains once unlocked; fused results cannot be fused again.