Experienced troop leaders know how to take advantage of gaps and secret passages in Fortresses in order to make surprise attacks on enemies. Upgrading this Knowledge increases your army's offense in battles for Fortresses.
| Level | Gold | Soul Shard | Time | Requirements | Troop Offense in Fortresses | Influence | Hero’s Experience |
| 1 | 140K | 28K | 54w 6d 00h 00m 00s> 1 Year(s) | Troop Offense When Guarding Fortresses II 1, Oracle 36 | 1% | 19K | 48.5K |
| 2 | 215K | 41K | 81w 2d 00h 00m 00s> 1 Year(s) | Troop Offense When Guarding Fortresses II 2, Oracle 36 | 3% | 43K | 61K |
| 3 | 285K | 61K | 120w 5d 00h 00m 00s> 2 Year(s) | Troop Offense When Guarding Fortresses II 3, Oracle 37 | 6% | 97K | 77K |
| 4 | 360K | 90.5K | 179w 2d 00h 00m 00s> 3 Year(s) | Troop Offense When Guarding Fortresses II 4, Oracle 37 | 9% | 220K | 97K |
| 5 | 430K | 135K | 266w 1d 00h 00m 00s> 5 Year(s) | Troop Offense When Guarding Fortresses II 5, Oracle 37 | 14% | 495K | 125K |
| 6 | 505K | 200K | 395w 2d 00h 00m 00s> 7 Year(s) | Troop Offense When Guarding Fortresses II 6, Oracle 38 | 19% | 1.15M | 155K |
| 7 | 595K | 300K | 83w 6d 00h 00m 00s> 1 Year(s) | Troop Offense When Guarding Fortresses II 7, Oracle 38 | 25% | 2.55M | 190K |
| 8 | 715K | 440K | 871w 4d 00h 00m 00s> 16 Year(s) | Troop Offense When Guarding Fortresses II 8, Oracle 38 | 32% | 5.7M | 235K |
| 9 | 950K | 655K | 1 294w 2d 00h 00m 00s> 24 Year(s) | Troop Offense When Guarding Fortresses II 9, Oracle 39 | 40% | 13M | 290K |
| 10 | 1.45M | 970K | 274w 4d 00h 00m 00s> 5 Year(s) | Troop Offense When Guarding Fortresses II 10, Oracle 39 | 50% | 29M | 355K |
| 5.65M | 2.92M | 3 621w 6d 00h 00m 00s> 69 Year(s) | 50% | 52.27M | 1.63M |
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