Fun animal "bits" for brainstorming and/or throwing at PCs:

* Critters of all sizes, insects on up, that are attracted to some
attribute of them and/or their equipment - their heat, their CO2 output,
their EM emissions (light, radio, etc).  A nuisance, or something more
serious.

* Trappers that are optimized to hunt something entirely different as
their usual prey, but have holes, lures, etc that are just the right
size for an unwary PC to step in, get a hand stuck to, walk into...

* A pouncer or chaser attack, not on the PCs, but on some hapless prey
animal very close by - possibly chasing it into their midst.

* Sound mimics; most of ours are birds, but they could look like anything.

* Something that's very venomous or poisonous (not the same thing) to
other things in its biosphere, and which behaves as such (warning
displays, etc), but which has different effects on PC biology, ranging
from "harmless" to "mild rash" to "euphoria, hallucinations, bad trips..."

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Kelly St. Clair
xxxxxx@efn.org