The Pointdexter is modelled after a blowfish and is found in large bodies of water. It has a grey, almost-spherical body, a blue face at its front which always frowns, and a blue occiput tail. There are numerous holes on the Pointdexter's body through which sharp steel spikes emerge.
Sonic the Hedgehog 3
Pointdexters are encountered in large bodies of water in the Hydrocity Zone. They float about slowly from side-to-side, occasionally extending their spikes. The player will take damage if they attack while the Pointdexter's spikes are revealed, so the player will need to time their attacks carefully.
Pointdexters appear once more in Hydrocity Zone. Their appearance and behaviour remain unchanged from Sonic 3.
Sonic the Comic
Pointdexters have appeared in numerous issues of the UK-published Sonic the Comic, debuting in Issue #33. Unlike their video game counterparts, they function in the air rather than water, apparently replacing the Bubbles Badnik that appears in the games.
The first time Sonic encountered a Pointdexter in the comic, he regarded it as the "dumbest-looking Badnik" that Dr. Robotnik had ever created. Just as he attacked it, however, the Pointdexter stuck out its spikes. Sonic just narrowly generated his "Insta-Shield" to avoid being gored while the Pointdexter flew away with its spikes bent out of shape.