Upgrading your Keep raises your unit cap and battle resource regen, and unlocks new buildings.
| Keep level | Unit cap | Resource regen | Cost |
|---|---|---|---|
| Keep Level 1 | 10 | +0 | 0g |
| Keep Level 2 | 12 | +1 | 60g |
| Keep Level 3 | 14 | +2 | 180g |
| Keep Level 4 | 16 | +3 | 460g |
| Keep Level 5 | 18 | +4 | 1170g |
| Keep Level 6 | 21 | +5 | 2830g |
| Keep Level 7 | 24 | +6 | 6580g |