I bought some at 'just got back legs' stage and fed them on bloodworm. I, too, had one that only had back leg stubs and was not eating the bloodworm. The others left it well behind in growth and I had to separate it because of the huge size difference. I put it in a tub of its own and moved it somewhere warmer (21 degrees) and fed it on daphnia and white worms for a couple of weeks (because I could get hold of these foods), then started it on small bloodworms. After a couple of months it caught up with the others in size. I'm keeping this one. Its called Blip and you'll find a picture of it on the cute axie thread.
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