Soldier
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LVL:2
HP: 60
DMG: 10
Speed: 1
Upgrades: HP+ V2
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BUYING
DMG+ V1, V2, V3 [10+20+30=60]
Soldier's level reaches 5 that makes Raider recieving +1 lvl [Level 6], so Soldier is able to get another upgrade.
If I'm right
HP+ V3 [30]
Total of 90 Bugfrags
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RESULTS
LVL: 6
HP: 70
DMG: 25
Speed:1
Bufrags left: 23