(also, I'd provide WCP links but their linking system is complicated. When I have the NPC ID it's far easier to generate a Wowhead link)
OLD:
- Glowing Sporebat : randomly changes between 2 colours: grey and blue (WCP only lists blue), so you only need to buy one. It appears as blue far less frequently (1 in 10 times). Purchased in Draenor Garrison.
- Amethyst Softshell : 2 looks: 1 colour, but smooth and spiked shell variants
- Blackchasm Crawler : 2 looks: 1 colour, but smooth and spiked shell variants
- Crimson Octopode : 2 looks: 1 colour, but with or without eyepatch
- Junkheap Roach : 2 colours: black and purple
- Malfunctioning Microbot : 3 looks: blue eyes, rotating red light, spray nozzle. One body colour.
- Mechagon Marmot : 2 colours: beige and slightly reddish beige. I’m unsure the one depicted on WCP is correct for either
- Microbot XD : 2 looks: blue eyes, rotating red light. One body colour. Blue eyes is less frequent (1 in 10)
- Motorized Croaker : 3 colours: green, mid brown, maroon
- Nameless Octopode : 2 looks: 1 colour, but with or without eyepatch. Eyepatch variant is much less frequent: 1 in 100!
- OOX-35/MG : 4 colours: gold, black with green, brown, black with brown
- Prismatic Softshell : 2 looks: 1 colour, but smooth and spiked shell variants
- Scrapyard Tunneler : 3 colours: green, maroon and grey-brown
- Spireshell Snail : 6 looks: composed of all combinations of 3 colours (green, yellow-brown and blue-tinted) and two shell styles (smooth and spiked)