My wife likes playing Moose Farkle and Penguin Farkle, a game of six dice in which the one is replace by the animal, and she asked if there was a Kitty Farkle. Until today, there wasn't. I grabbed a cat cartoon she had drawn on a post-it on the fridge door, turned it into an .stl and slapped it onto a dice model. Print 6x -- in Resin for extra weight -- push some sugru into the pip cavities, and BOOM. Kitty Farkle. Giving it to her in a nice wooden box for Christmas.
This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/lCQvDx3mXkN
Modifed a standard die design with Tinkercad
Modified Dice .stl replacing the "one" pip with a cat. The cat was drawn by my wife, I made a high contrast image of her line drawing and filled in the negative space. That meant I had to do some inversion where the arm crossed the body and the whiskers extended past the face. I uploaded the image at Selva3D and converted it into an .stl file, then imported that into Tinkercad. Converted it to a hole and sunk it to the same depth as the pips.
Printed the resulting file in standard white resin with Omni's Hub in Boxtel (Highly recommend!) and then applied royal blue Sugru to the pip cavaties. Had to work reasonably fast to finish 8 dice before the Sugru set.