| “ | In the Inventor's Workshop you can research and upgrade your defensive fortification technologies. By upgrading the technology, you are able to strengthen your line of defense and protect your kingdom and its treasure. | „ |
The maximum level you can upgrade a structure is shown in the tables below. You can level up a construction for 3 or 4 times. Each time you upgrade a plan, you will allow to upgrade that at the Maximum Research Level listed near the column of plans. So if you want to upgrade an Arrow Tower to level 6, you have first to upgrade "Plan Arrow Tower level 2" that allow you to upgrade then it.
Maximum research levels
Edit
| Levels → | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Barricade | 1 | 2 | 2 | 2 | 3 | 3 | 3 | 4 | 4 | 4 | 4 | 4 | 4 |
| Arrow Tower | 1 | 1 | 2 | 2 | 2 | 2 | 3 | 3 | 4 | 4 | 4 | 4 | 4 |
| Spikes | 1 | 1 | 2 | 2 | 2 | 3 | 3 | 3 | 4 | 4 | 4 | 4 | |
| Bomb Tower | 1 | 1 | 1 | 2 | 2 | 3 | 3 | 4 | 4 | 4 | 4 | ||
| Frost Tower | 1 | 1 | 2 | 2 | 3 | 3 | 4 | 4 | 4 | 4 | |||
| Blockade | 1 | 1 | 2 | 3 | 3 | 4 | 4 | 4 | 4 | ||||
| Gargoyle Tower | 1 | 1 | 2 | 2 | 3 | 4 | 4 | 4 | |||||
| Firebolt Tower | 1 | 1 | 2 | 3 | 4 | 4 | 4 | ||||||
| Snake Tower | 1 | 2 | 3 | 4 | 4 | 4 | |||||||
| Skull Tower | 1 | 3 | 4 | 4 | 4 | ||||||||
| Lightning Tower | 3 | 3 | 4 | ||||||||||
| Heal Tower | 3 | 4 | |||||||||||
| Jester Box | 2 | 3 | |||||||||||
| Basilisk Tower | 1 | ||||||||||||
LevelsEdit
| Level | Requirement | Upgrade Cost | Upgrade Time |
|---|---|---|---|
| 1 | Throne Room level 1 |  1K
|  2m
|
| 2 | 3K
| 10m
| |
| 3 | Throne Room level 2 | 10K
| 30m
|
| 4 | Throne Room level 3 | 25K
| 1h
|
| 5 | Throne Room level 4 | 50K
| 4h
|
| 6 | Throne Room level 5 | 100K
| 12h
|
| 7 | Throne Room level 6 | 250K
| 1d
|
| 8 | Throne Room level 7 | 500K
| 2d
|
| 9 | Throne Room level 8 | 1M
| 3d
|
| 10 | Throne Room level 9 | 2M
| 4d
|
| 11 | Throne Room level 10 | 6M
| 5d
|
| 12 | Throne Room level 11 | 8M
| 6d
|
| 13 | Throne Room level 12 | 10M
| 7d
|
Plan BarricadeEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 1 | |
| 2 | 6 | 25K
| 3h
| |
| 3 | 9 | 150K
| 1d
| |
| 4 | 20 | 350K
| 2d
| |
Plan Arrow TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 1 | |
| 2 | 6 | 50K
| 4h 30min
| |
| 3 | 9 | 250K
| 1d 12h
| |
| 4 | 19 | 750K
| 3d
| |
Plan SpikesEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 2 | |
| 2 | 6 | 50K
| 4h 30min
| |
| 3 | 9 | 250K
| 1d 12h
| |
| 4 | 20 | 750K
| 3d
| |
Plan Bomb TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 3 | |
| 2 | 6 | 150K
| 4h 30min
| |
| 3 | 9 | 750K
| 1d 12h
| |
| 4 | 18 | 1M
| 3d
| |
Plan Frost TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 4 | |
| 2 | 6 | 250K
| 4h 30min
| |
| 3 | 9 | 750K
| 1d 12h
| |
| 4 | 18 | 1.25M
| 3d
| |
Plan BlockadeEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 5 | |
| 2 | 6 | 150K
| 4h 30min
| |
| 3 | 9 | 750K
| 1d 12h
| |
| 4 | 18 | 1.5M
| 3d
| |
Plan Gargoyle TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 6 | |
| 2 | 6 | 1M
| 1d 18h
| |
| 3 | 10 | 2M
| 3d 12h
| |
| 4 | 16 | 3M
| 5d 6h
| |
Plan Firebolt TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 7 | |
| 2 | 6 | 2M
| 2d 6h
| |
| 3 | 10 | 3.5M
| 4d 12h
| |
| 4 | 16 | 5M
| 5d
| |
Plan Snake TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 8 | |
| 2 | 6 | 1M
| 2d
| |
| 3 | 10 | 2.5M
| 3d
| |
| 4 | 16 | 3.5M
| 4d
| |
Plan Skull TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 9 | |
| 2 | 6 | 3M
| 2d 6h
| |
| 3 | 9 | 4M
| 3d 9h
| |
| 4 | 15 | 5M
| 4d 12h
| |
Plan Lightning TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time | |
|---|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 11 | ||
| 2 | 6 | 4M
| 2d 6h
| ||
| 3 | 9 | 5M
| 3d 9h
| ||
| 4 | 10 | 6M
| 4d 12h
| ||
Plan Jester BoxEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 12 | |
| 2 | 6 | 4M
| 2d
| |
| 3 | 7 | 5M
| 3d
| |
Plan Heal TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 12 | |
| 2 | 6 | 4M
| 2d 6h
| |
| 3 | 9 | 5M
| 3d 9h
| |
| 4 | 10 | 6M
| 4d 12h
| |
Plan Basilisk TowerEdit
| Picture | Level | Max. Research Level | Upgrade Cost | Upgrade Time |
|---|---|---|---|---|
 | 1 | 3 | Unlock Inventor's Workshop level 13 | |
