The Combat Research Upgrade: Infected Among Us increases the attack power of all your infected troops. Requires Level 9 Research Lab and Level 1 Runner.
| Level | Infected Attack Power |
|---|---|
| 1 | +1% |
| 2 | +3% |
| 3 | +7% |
| 4 | +13% |
| 5 | +21% |
| 6 | +31% |
| 7 | +46% |
| 8 | +66% |
| 9 | +91% |
| 10 | +131% |