Drawn-out confrontations can exhaust even an experienced warrior. Train your soldiers in times of peace and they will be able to last through even the most grueling battles! This Study increases the maximum amount of Hero’s Stamina.
| Level | Food | Lumber | Iron | Stone | Silver | Gold | Time | Requirements | Increased Maximum Hero's Stamina Reserve | Power | Hero's Experience |
| 1 | 4K | 2.5K | 0 | 2.5K | 5K | 520 | 01h 00m 00s | 25 | 250 | 12.5K | |
| 2 | 10.5K | 6.35K | 0 | 6.35K | 11.5K | 835 | 05h 00m 00s | Academy 9 | 65 | 575 | 16K |
| 3 | 26K | 16.5K | 0 | 16.5K | 26.5K | 1.6K | 13h 00m 00s | Academy 10 | 120 | 1.35K | 21K |
| 4 | 65.5K | 41K | 0 | 41K | 61K | 3.2K | 1d 09h 00m 00s | Academy 11 | 190 | 3.05K | 26.5K |
| 5 | 170K | 105K | 0 | 105K | 140K | 6.9K | 3d 09h 00m 00s | Academy 12 | 275 | 7K | 34.5K |
| 6 | 420K | 265K | 0 | 265K | 325K | 17K | 1w 2d 00h 00m 00s | Academy 13 | 375 | 16.5K | 44K |
| 7 | 1.1M | 665K | 0 | 665K | 745K | 36.5K | 3w 00h 00m 00s | Academy 15 | 490 | 37.5K | 56.5K |
| 8 | 2.7M | 1.7M | 0 | 1.7M | 1.75M | 82.5K | 7w 2d 00h 00m 00s | Academy 17 | 620 | 85.5K | 72.5K |
| 9 | 6.85M | 4.3M | 0 | 4.3M | 3.95M | 195K | 18w 2d 00h 00m 00s | Academy 19 | 765 | 200K | 93.5K |
| 10 | 17.5M | 11M | 0 | 11M | 9.05M | 460K | 45w 3d 00h 00m 00s | Academy 21 | 925 | 455K | 120K |
| 28.85M | 18.1M | 18.1M | 16.06M | 804.06K | 76w 13h 00m 00s> 1 Year(s) | 925 | 806.73K | 497K |
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