Li lungs probably are the weirdest looking dragons ever, looking more like a cross between a lammasu and a peacock.
Tatalla, whose name means "the eye", are malicious little creatures often employed as spies or assassins by larger creatures. Tatalla reside only in urban areas, where their services are often desired, and where they are never far from vermin to aid them in their tasks. Tatalla are scavengers, living off the remains of society. They steal what they need and give nothing back to society or to their environment.
The original unbodied were humans who became too smart for this world and ascended to a higher plane of existence. The remaining unbodied are beings of pure mind that can assume any illusory form.
Udoroot is a sessile monster whose main part is buried underground. Its sunflower-like crows manifest psionic abilities and use other creatures as fertilizer.
Thought eaters are bestial aberrations with transparent flesh. They can drain mental energies and shift between the Ethereal and the Material planes. Thought slayers are stronger, bigger, and scarier.
This is a fun psionic monster than grapples its prey and timeports it 7 minutes in the future, where (when?) its likely to be without its companions.
Puppeteers are tiny creatures that attach to living hosts, drain sustenance from them, and control them. Flesh harrowers (also known as dire puppeteers) have a big maw.
At first, I didn't even want to include this as a lens. A phrenic creature is just a psionically gifted and psionically resistant normal creature.
The gray glutton is a biological weapon created by some unknown arcane spellcasters (probably elves, considering the racial quirk) who were persecuted by the psis in the ancient past. Fun!
This is probably my favorite monster from the Expanded Psionics Handbook. It's relatively simple, can be used both as an ally or an enemy, has some psionic abilities, and it looks very pleasant. What is not to like?
Brain moles are pests that are attracted to psionic energies, but themselves are invisible to psionic detection. They spread cascade flu - a contagious disease that makes psionic powers manifest uncontrollably.