Thanks to the new armor of tempered steel your killers will be much better protected — a great advantage in battle! Upgrading the Knowledge improves the defense of your killers.
| Level | Lumber | Iron | Stone | Silver | Gold | Time | Requirements | Increased Killer Defense | Influence | Hero’s Experience |
| 1 | 5K | 3.75K | 5K | 4K | 860 | 04h 30m 00s | 1 | 200 | 15K | |
| 2 | 10K | 7.5K | 10K | 10K | 1.4K | 10h 00m 00s | Oracle 5 | 3 | 500 | 30K |
| 3 | 20K | 15K | 20K | 25K | 2.65K | 1d 00h 00m 00s | Oracle 7 | 7 | 1.25K | 45K |
| 4 | 40K | 30K | 40K | 62.5K | 4.55K | 2d 00h 00m 00s | Oracle 9 | 13 | 3.15K | 60K |
| 5 | 80K | 60K | 80K | 160K | 9.1K | 4d 12h 00m 00s | Oracle 11 | 21 | 7.85K | 75K |
| 6 | 160K | 120K | 160K | 395K | 19K | 1w 3d 00h 00m 00s | Oracle 13 | 31 | 20K | 90K |
| 7 | 320K | 240K | 320K | 980K | 36K | 3w 1d 00h 00m 00s | Oracle 15 | 46 | 49K | 105K |
| 8 | 640K | 480K | 640K | 2.45M | 64.5K | 6w 5d 00h 00m 00s | Oracle 17 | 66 | 125K | 120K |
| 9 | 1.3M | 960K | 1.3M | 6.15M | 120K | 14w 5d 00h 00m 00s | Oracle 19 | 91 | 310K | 135K |
| 10 | 2.6M | 1.95M | 2.6M | 15.5M | 215K | 32w 3d 00h 00m 00s | 131 | 765K | 150K | |
| 5.18M | 3.87M | 5.18M | 25.74M | 473.06K | 59w 4d 02h 30m 00s> 1 Year(s) | 131 | 1.28M | 825K |
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