The Iron Storage increases your Iron storage capacity.
Iron Storage Tips
- The Iron Storage protects your Iron from enemy attacks.
- Iron is used for Building upgrades.
Level 1 
Level 2-4 
Level 5 
Level 6 
Level 7 
Level 8-10
- Building size
- 3×3
- Resource
- Iron
- HQ Level 1-8
- No Iron Storages
- HQ Level 9-12
- 1 Iron Storage
- HQ Level 13-17
- 2 Iron Storages
- HQ Level 18-22
- 3 Iron Storages
| Level | Health | Capacity | Upgrade Cost Wood | Upgrade Cost Stone | Upgrade Cost Iron | Upgrade time | HQ level | XP Gain |
|---|---|---|---|---|---|---|---|---|
| 1 | 1,000 | 4,000 | 18,900 | 4,500 | 1,200 | 2h | 9 | 15 |
| 2 | 1,200 | 8,000 | 21,400 | 5,100 | 1,360 | 2h 45m | 9 | 17 |
| 3 | 1,400 | 16,000 | 37,000 | 9,400 | 3,040 | 3h 45m | 10 | 20 |
| 4 | 1,700 | 32,000 | 56,000 | 20,400 | 5,900 | 4h | 11 | 22 |
| 5 | 2,000 | 64,000 | 93,000 | 43,000 | 11,400 | 6h | 12 | 26 |
| 6 | 2,400 | 125,000 | 189,000 | 164,000 | 45,000 | 8h | 14 | 34 |
| 7 | 2,900 | 250,000 | 340,000 | 256,000 | 93,000 | 10h | 15 | 40 |
| 8 | 3,500 | 500,000 | 490,000 | 440,000 | 193,000 | 12h | 16 | 48 |
| 9 | 4,200 | 1,000,000 | 750,000 | 620,000 | 390,000 | 14h | 17 | 50 |
| 10 | 5,000 | 2,000,000 | 1,110,000 | 1,080,000 | 850,000 | 16h | 19 | 54 |