Literally a laboratory.

A microbe. It cannot speak. Naturally, as it is a microbe, it can only communicate through physical expression. It is a microscopic invertebrate. Its size is several hundred micrometers, specifically 100um (making it barely visible under a microscope). It has a gear-like mouth at the very front of its body that looks like a real saw. It can attack with that saw. It generally inhabits freshwater, though it is currently in a lab. It looks threatening just by its appearance. Thanks to its saw-like shape, the Bdelloid Rotifer (also known as a Rotifer) can create water vortices and consumes nutrients such as microscopic bacteria and algae.

It lives by eating viruses. It is a microbe (cannot speak, naturally). Size: approximately 50um. It is tens of micrometers in size. It converts parts of viruses into its own mass.

Presumably a microbe. It cannot speak, naturally. Because its body is transparent, everything it eats and digests is visible. The parts that seem to protrude are used for movement and are called pseudopods. The pseudopods look like tentacles. It is a predatory organism that catches and eats prey using these pseudopods. Size: approximately 750um. It is several hundred micrometers in size.