The Copper Key is a common key. It is used to unlock a Locked Copper Chest.
Obtaining
Crafting
| Materials | Crafting station |
|---|---|
 Copper Bar (5) |  Key Casting Table |
Fishing
| Source | Catch type | Chance |
|---|---|---|
 Normal water Undergrounds + Normal water | Loot | 2.36% |
Drops
| Source | Chance for one | Chance per roll |
|---|---|---|
 Large Wooden Crate | 2.06% | 0.59% (3–4) |
 Orange Slime | 1.17% | 1.17% (1) |
 Red Slime | 1.1% | 1.1% (1) |
 Small Slime Vessel | 1.17% | 1.17% (1) |
Structure-exclusive loot
| Structure | Container | Chance for one | Chance per roll |
|---|---|---|---|
| Bridge Area Wood House Abandoned Camp Hidden Clay Chest Hidden Turf Chest Small Islands |  Chest | 5.92% | 1.35% (4–5) |
| Clay Melody Room (style 1) |  Copper Chest | 100% | 100% (1) |
| Main Larva Hive Small Larva Hive Clay Melody Room (style 2) |  Larva Hive Chest | 8.7% | 2.25% (3–5) |
History
- 1.0.0.1: Sell value decreased from 6
to 5 . - 0.5.2.0-b84a:
- Reduced the cost of crafting keys at the Key Casting Table.
- Keys now also have a small chance to drop from all types of slimes, Cavelings, and from fishing.
- 0.5.0.0-9b96: Introduced.
