Free Upgrades provide a chance for an upgrade to level up for free after each wave.
There are three Free Upgrades, one for each workshop:
| ‣ | Type | Description | Unlock Cost | Max Level | Max Enhancement | Upgrade Costs |
|---|---|---|---|---|---|---|
| Free Upgrades+ | ‣ | Applier a multiplier to Free Attack Upgrades, Free Defense Upgrades, Free Utility Upgrades. Starts at 1x and increases by 0.01x per level. | 5 trillion ‣ spent on Utility Enhancements | 50 | 1.5x bonus | See Wiki for level costs. |
https://the-tower-idle-tower-defense.fandom.com/wiki/Free_Upgrades#Overview