Swarm of Piranhas
Medium Swarm of Tiny Beasts · · CR 1
- Swarm of Tiny Beasts
- Medium
- Tier 1
Ranges across underwater; Swarm of Piranhas lists at CR 1 as a medium swarm of tiny beasts (unaligned). Sourced from Monster Manual (5.5e 2024).
Stat Block
- Challenge Rating
- 1
- Type
- Swarm of Tiny Beasts
- Size
- Medium
- Alignment
- —
- Speed
- —
- Habitats
- Underwater
- Sources
- Monster Manual (5.5e 2024)
Ecology
Piranhas dominate warm freshwater ecosystems where prey is abundant. A swarm forms when individual fish detect blood in the water, triggering a feeding frenzy that draws nearby piranhas across vast distances. They strip carcasses in seconds, leaving only bones to wash downstream. Piranhas tolerate harsh water conditions and breed prolifically, making elimination nearly impossible. Crocodiles and giant fish prey on individuals, but no predator efficiently targets the swarm itself.
Behaviour
Piranhas are surprisingly cautious in the absence of stimulus, schooling quietly and avoiding shadows above the water. The instant blood reaches them, all caution evaporates. They will bite anything moving, including each other, and a swarm in frenzy can self-cannibalize when prey runs out. After feeding, the school disperses temporarily to digest. Captive piranhas can be conditioned to feed on schedule, but escapees revert to wild instinct within hours.
Origin
Native to tropical river systems, piranhas were spread to other regions by misguided sahuagin traders and dragon turtle bait stocks. Some druids claim piranhas are the river's vengeance, summoned by murdered tribes to drain colonizers. The truth is more mundane: they are remarkably efficient predators that thrive wherever introduced, displacing native fish and reshaping the food web within a generation.
Related Monsters
Frequently Asked Questions about Swarm of Piranhas
- What is the challenge rating of Swarm of Piranhas?
- The CR on Swarm of Piranhas is 1. That CR works against tier-1 parties.
- What type of creature is Swarm of Piranhas?
- Swarm of Piranhas is classified as a swarm of tiny beasts in D&D 5e, medium size.
- Where does Swarm of Piranhas live?
- The published habitats for Swarm of Piranhas: Underwater.