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 | 175K | 34.5K | 68w 3d 00h 00m 00s> 1 Year(s) | Troop Offense When Guarding Fortresses III 1, Oracle 36 | 1% | 16K | 40K |
| 2 | 265K | 51.5K | 101w 5d 00h 00m 00s> 1 Year(s) | Troop Offense When Guarding Fortresses III 2, Oracle 36 | 4% | 35.5K | 50.5K |
| 3 | 355K | 76K | 150w 6d 00h 00m 00s> 2 Year(s) | Troop Offense When Guarding Fortresses III 3, Oracle 37 | 8% | 80.5K | 64K |
| 4 | 445K | 115K | 224w 1d 00h 00m 00s> 4 Year(s) | Troop Offense When Guarding Fortresses III 4, Oracle 37 | 13% | 185K | 80.5K |
| 5 | 540K | 170K | 332w 5d 00h 00m 00s> 6 Year(s) | Troop Offense When Guarding Fortresses III 5, Oracle 38 | 19% | 410K | 105K |
| 6 | 635K | 250K | 494w 1d 00h 00m 00s> 9 Year(s) | Troop Offense When Guarding Fortresses III 6, Oracle 38 | 26% | 925K | 130K |
| 7 | 740K | 370K | 733w 5d 00h 00m 00s> 14 Year(s) | Troop Offense When Guarding Fortresses III 7, Oracle 39 | 34% | 2.1M | 160K |
| 8 | 895K | 550K | 1 089w 3d 00h 00m 00s> 20 Year(s) | Troop Offense When Guarding Fortresses III 8, Oracle 39 | 45% | 4.75M | 195K |
| 9 | 1.2M | 815K | 1 617w 6d 00h 00m 00s> 31 Year(s) | Troop Offense When Guarding Fortresses III 9, Oracle 40 | 56% | 11M | 240K |
| 10 | 1.85M | 1.25M | 2 402w 3d 00h 00m 00s> 46 Year(s) | Troop Offense When Guarding Fortresses III 10, Oracle 40 | 70% | 24M | 295K |
| 7.1M | 3.68M | 7 215w 3d 00h 00m 00s> 138 Year(s) | 70% | 43.5M | 1.36M |
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