Bloon Bleed is a status effect introduced in Bloons Adventure Time TD. It is characterized by visibly large scratches (BTD6) or a hole through which air leaks out (BATTD) on the affected bloon(s), causing affected bloons to slowly lose health. It was later introduced in Version 24.0 of Bloons TD 6 with the arrival of Sauda.
Bloon Bleed is represented on the Bloons Wiki with 
, which depicts the icon for Deflation Mode in Bloons TD 6. This is because there is no other suitable icon that distinctly represents the deflation of a bloon. In fact, the "bleed" of a bloon is not the oozing of red blood that would come out of vertebrate creatures but instead is the expulsion of air from inside the bloon. Visually, in addition to visibly large scratches is a regular puffing of air out of the affected bloon(s), representing what would normally be the oozing of blood in the case of realistic non-cartoonish violence.
Bloons affected by Bloon Bleed in BTD6 are dealt 2 damage per 2.0s (5 damage per second in BATTD), or 20 damage for MOAB-class bloons. It never expires in BATTD, but in BTD6 it lasts for up to 4 seconds. In BTD6, Bloon Bleed's duration is refreshed by getting hit again with an attack containing this status effect. Unlike other status effects, Sauda's Level 11+ Extra Damage to Harmed 
does not count Bloon Bleed as a valid status effect in the case of adding extra damage per hit.
The COBRA's Attrition upgrade is the status effect's sole source in Bloons Adventure Time TD, while only Sauda is capable of inflicting this status effect in Bloons TD 6.
Trivia
- According to Ninja Kiwi's 3rd September 2021 blog, when asked the question "If the bloons bleed, given that Sauda can inflict Bloon Bleed, does this mean Bloons actually have tough flesh?", Ninja Kiwi appears to be afraid of how much lore is exposed from that question alone.
