Fields of Mistria: Mining Floors and Biome Seals
Break every biome seal to keep going deeper. Seals sit on floors 20, 40, 60, 80, and 90. Here are the exact items, farming routes, and the mistakes that stall players.
Goal: Break each biome seal so you can keep going down the mines. Seals sit on floors 20, 40, 60, 80, and 90+. You cannot skip them. Players get stuck because they sold the one fish, bug, or forage the seal wants, or they grind the wrong floors for Void items. Keep at least one of every mine fish, bug, forage, and gem until that biome's seal is done.
Mine Layout at a Glance
| Biome | Floors | Seal | Seal Floor |
|---|---|---|---|
| Upper Mines | 1-19 | Water Seal | 20 |
| Tide Caverns | 21-39 | Earth Seal | 40 |
| Deep Earth | 41-59 | Fire Seal | 60 |
| Lava Caves | 61-79 | Ruins / Void line | 80 |
| Ancient Ruins | 81-99 | Floor 90 key / last stretch | 90+ |
1Water Seal (Floor 20) - Unlock Tide Caverns
Offer all four from the Upper Mines:
- Ruby - mine ruby nodes
- Upper Mines Mushroom - forage on the floor (brown round-top mushroom)
- Stone Loach - fish any water pool in floors 1-19
- Lantern Moth - catch in Upper Mines
2Earth Seal (Floor 40) - Unlock Deep Earth
Offer from Tide Caverns:
- Sapphire - sapphire nodes, often near water
- Jade Dulse - forage
- Archerfish - fish Tide pools (medium-rare, usual time sink)
- Coral Mantis - bug in Tide
3Fire Seal (Floor 60) - Unlock Lava Caves
This is the first seal that is not just four local drops. Players stall here on gems and Balor.
From Deep Earth (41-59):
- Emerald - emerald nodes
- Rockroot - forage
- Faceted Rock Gem - dig spots (Archaeology perk helps)
- Sealing Scroll from Balor - talk to Balor after the floor 60 tablet, donate to his box, complete his trade
Balor's scroll costs (community-reported):
- 10 Silver Ingots - smelt Deep Earth silver
- 10 Sapphires - from Tide
- 10 Emeralds - from Deep Earth
- 10 Rubies - from Upper Mines
4Floor 80 - Void Prep and Ruins Seal
Step A - Farm Void materials (5 each):
- Void Pearls - fishing (any fish, any size)
- Void Powder - kill any monsters
- Void Herbs - forage (only visible with Void Sight)
- Void Stones - mining / floor scan
Step B - Ruins Seal offerings (Lava Caves 61-79):
- Smoke Moth
- Breath of Flame - forage
- Obsidian
- Firesail Fish - the bottleneck
5Floor 90+ - Key, Door, and Written Root
Floor 90 has its own quest: find a key and open the door to go deeper. Late ingredients include monster parts, remaining Void items, 4 Medium Essence Stones, 2 Mistril Ingots, 2 Pink Diamonds, Luminescence Crab, Ancient Firefly, Void Snail, and Written Root.
Quick Decision Guide
Common Mistakes to Avoid
- Selling unique mine fish, bugs, or forage "for space." Keep one of each until that biome's seal is done.
- Clearing every rock on every floor. You waste the day and still miss forage. Scan, grab, ladder.
- Fishing with enemies in range. Firesail despawns when combat starts. Clear first, cast second.
- Farming Void stuff only in Lava. Void drops appear in every biome. Upper Mines and Tide are faster.
- Spending 10+10+10 gems before Balor's scroll. Buy the scroll first, then upgrade tools.
- Jumping elevator floors too fast. Players have reported game hitches and crashes while monster-farming this way.