Carnivorous Plant
Carnivorous plants are plants that derive at least some of their nutrients from trapping and killing animals or microbes, rather than through photosynthesis. Fiction is rife with examples of man-eating plants, especcially RPGs, given how easily they fit into the role of Gotcha Monster.
IRL: carnivorous plants live in nutrient and mineral poor environment, mostly bogs, and make up the difference with insects they catch. As such adding a few carnivorous plant monsters would be a good fit to any swamp environment
Dungeons & Dragons
- Assassin Vine or Choke Creeper: A predatory vine-like plant that drapes itself across tree branches, and attempts to strangle any animal that gets within range.
- Bloodroot: Roots that stick out of the sides of underground passageways. When something passes by them, they grab it, inject it with a blood-thinning poison, and suck out all its liquids.
- Bloodthorn: Yet another bloodsucking vine. This one is native to the Lower Planes.
- Bohun Tree: The fruits of this tree resemble giant grapes, but if bruised or damaged in any way, they release a soporific vapor that has a 10% chance of paralyzing your lungs and killing you. The tree will deliberately burst its own fruit if attacked. It is also covered in thorns that can be fired off of it as projectiles. It can also send its roots up through the ground to grab you. Appeared in Dragon #89.
- Boneleaf: An aberration that resembles a plant. It is intelligent and can use illusions to lure prey. All boneleaves in an area are actually parts of a single organism so what one learns, all boneleaves nearby also learn.
- Crawling Ivy: Prehensile ivy that has tiny pores all over its leaves that it uses to suck out your blood.
- Ironmaw: A carnivorous tree that can disguise itself as any other type of tree. Native to the Outer Planes.
- Vampire Rose or Bloodrose: White roses that turn red after soaking up a creature's blood. They remain motionless until an animal wanders into the center of their patch, then tear it open with their thorny tendrils.
- Yellow Musk Creeper
- A pretty creeping vine with beautiful yellow flowers. It lures victims in with its sweet scent, and then plants seeds in their heads, which consume the host's brain and then hijack the body as a zombie they pilot to find a new place to grow.