So this has been due for a while!
I don't believe I've posted any of Mia's newer art since her 2021 redesign. In case you haven't been acquainted, Mia is my 3rd-to-main sona (behind Ray and Grey). She's a lovable, squishy goo dragon-cat thing made of soft, comfy rubber. Or more accurately, a hyper-elastic living latex nanopolymer! This allows her to shapeshift and change forms with ease. Given that her body is entirely made up from the same type of 'cells', she's naturally entirely null, lacking a face whatsoever, though she sees through a sort of 3D 'radar' around her in all directions.

Mia was created in a lab as yet another attempt to create the most powerful Pokemon via cloning Mew. In this case, primarily Mew and Goodra DNA, with some ditto blended in. And for the most part, they succeeded. Mia is effectively indestructible. When impacted, she simply absorbs the energy with her rubber mass. And when sliced, it only causes her to multiply! Her mass is synthetic, nonreactive, and nonmagnetic, and poisons and acids have little to no effect. Attempting to absorb/consume Mia will always lead to Mia taking control of the absorber's body.

Mia can self-replicate as well, creating clones of herself with effectively no limit! Her shapeshifting allows her to form all sorts of things, from disguising herself as other beings (replication of color/texture, clothes, voice, etc.), to weapons (which generally fire rubber bullets that engulf the target in a rubber containment suit), to even vehicles (her favorite vehicle form is a plane/spacecraft, which while appearing to be made of metal, is entirely soft and squishy to the touch!) Her psychic abilities further enhance this, allowing her to play tricks on your mind, use telekinetics to fly or hover objects, and sense others from a distance.

Her only weaknesses are relatively low intelligence (not an idiot, but is quite gullible), slow reaction time (due to the nature of her distributed processing system), and certain extreme conditions. Extreme cold (near absolute zero) will freeze her in place (but won't stop her psychics), while an extreme impact (roughly a medium nuclear warhead) may trigger a hard system reboot... buying you a mere 6 seconds while she recalibrates.

There is no one solution to stopping Mia, but containment at extreme cold temperatures in a pressure-resistant vessel is the optimal way to store her. That said, if you leave even a drop unaccounted for, she'll only replicate, grow, and spread.

Art by me, shaded by  Huffzie