Cleansing Foam is an upgrade for the Engineer Monkey (or Monkey Engineer prior to BTD6), first released in BTD5 Generation. It grants the Engineer with an attack that produces foam around nearby track, removing Camo and Regrow properties as well as popping Lead Bloons. In BTD5 Generation games, foam is distributed sporadically, while in BTD6 and BTDB2 foam is focused on a specific location. Additionally, the Cleansing Foam upgrade follows from a different lineage of upgrades; BTD5 Generation games follow it along the sentry-related upgrades, while BTD6 and BTDB2 follow it along the "property management" upgrade path, which contains Larger Service Area.
The following pages correspond to the Cleansing Foam upgrade:
- Cleansing Foam (BTD5), the third upgrade of Path 2 for the Monkey Engineer in BTD5.
- Cleansing Foam (BTD6), the third upgrade of Path 2 for the Engineer Monkey in BTD6.
- Cleansing Foam (BTDB2), the third upgrade of Path 2 for the Engineer Monkey in BTDB2, nearly identical to its BTD6 counterpart.