Stronger Acid is the first upgrade on the second path for the Alchemist in BTD6. It makes the acid effect applied by the Alchemist (and any acid pools formed if that upgrade is purchased) deal overall increased damage, increasing its damage rate from 2.0 to 1.5 seconds, as well as increasing the duration of the acid effect from 4.0 to 4.5 seconds, giving the acid 3 damage ticks.
It costs $210 on Easy, $250 on Medium, $270 on Hard and $300 on Impoppable.
- When this upgrade is combined with either Acid Pool or Larger Potions, it becomes a moderately powerful tower early game against grouped bloons.
- Upgrading the Alchemist to this level, gives it gloves, suggesting that the acid is too dangerous to handle without them. The same applies to its subsequent upgrades.