Expedition 33 Chroma Catalyst Farm Guide
Break through weapon upgrade walls - early catalyst sources, the Endless Tower Duollistes loop, and endgame farms for Perfect Catalysts.
Core Problem: Chroma Catalysts (Grandiose and Perfect) are required to level weapons past mid-game breakpoints (~level 20 for Act 3 viability, max 33). Catalyst scarcity stalls progression. This guide gives you exact farming spots in order - from early dungeons to the fastest endgame loop that yields 20 Lumina + 5 Grandiose + 1 Perfect Catalyst per run.
1 Unlock Weapon Upgrades First
- Progress the story until Withers (the grunt-speaking NPC) joins your camp permanently.
- Talk to Withers at camp to access the upgrade menu - it does not appear at flags or early camp locations.
- Prioritize relationship levels at camp, especially Maelle's quest, to unlock more content and catalyst sources.
2 Early/Mid-Game Sources (Acts 2-3)
| Source | What it Drops | Notes |
|---|---|---|
| Endless Tower Trials 1-2 | 2x Grandiose Catalysts | Do this first - push 2 key DPS weapons to level 20 immediately |
| The Reacher dungeon | Many Grandiose + EXP | North of Endless Tower - run repeatedly in mid-game |
| Frozen Heart dungeon | Grandiose + EXP/levels | Near Monoco Trainstation - pair with Reacher runs |
| Dark Shore (Act 1 revisit) | Guaranteed Grandiose + high EXP | Big hand enemies are the target. Grind to level ~80 if needed before major story pushes |
| Merchants / Bosses | Polished / Resplendent catalysts | Buy from merchants when available; mini-bosses also drop on kill |
3 Endgame Farm: Endless Tower Duollistes Loop
The best balanced farm for Lumina + Catalysts + EXP. ~64-70 seconds per run at high level.
Setup Required
Party: Lune (main DPS), Merso, Sael (support). Equip speed Pictos so turn order is Lune → Merso → Sael.
HP setup: Enter characters at 1 HP. Use a random overworld fight with Auto Death + Survivor active, let one character die/flee, don't heal before the farm run. This maximizes specific combat mechanics.
Battle Rotation
-
1
Lune: Elemental Trick (build 4 stains) → basic attack (converts to dark stains).
-
2
Merso: Steel Strike (extra turn setup) → Phantom Stars (manage damage to control phase transitions; avoid perfect timing in some cases).
-
3
Sael: Fortune's Fury on Lune + Intervention on Merso.
-
4
Phase 2: Lune Lightning Dance to finish the fight.
Rewards per run:
4 Alternative Endgame Farms
- NG+1 Osquio battle: Similar low-HP setup and speed turn order, slightly different skill rotation. Faster/easier for some players. Still yields Perfects + catalysts.
- Golgra one-shots (Act 3, with Painted Power Picto): ~24k-29k Chroma per quick run. Best if weapons are the only bottleneck.
- Renoir's Drafts vendor loop: One-shot for Chroma + Lumina + EXP combined.
Key Decision Points
Common Mistakes to Avoid
- Spreading catalysts too thin early - upgrade only priority DPS weapons in Acts 2-3. Support units can wait until you have a surplus from endgame farms.
- Ignoring the Painted Power Picto - it's a dramatic damage multiplier for one-shot farming routes. Skipping it makes Golgra and similar farms much slower.
- Poor phase transition management in Duollistes - rushing or mistiming Phantom Stars in phase control wastes the run or causes a failed clear. Practice the rotation first.
- Forgetting Withers at camp - the upgrade menu only exists at camp with Withers present. Players who miss this stall for hours thinking upgrades are locked by story.
- Wrong turn order in Duollistes loop - speed Pictos must be equipped to enforce Lune → Merso → Sael order. Wrong order breaks the entire combo and doubles run time.
Video Guide
Step-by-step Duollistes farm - exact builds, timings, NG and NG+ methods with skill sequences (top community recommendation)