A 4" sculpin, a 4" swimbait, both mastered with sculpy clay, and molded with Alumilite RTV silicone.
The top swimbait in the second picture is 5", and was molded from GE clearseal, from a caulking gun.
The top two have hook slots in the belly.
I didn't think to add that to the sculpin, so I use a soldering gun with a flat blade tip to melt it into the finished bait. I'll probably figure out how to add an insert, but the bait is an open pour, belly up mold, so it's a little challenging.