For me, probably insects. I’ve been fascinated by insects when I was little, and honestly I feel like I’ve been getting back into it recently. I started keeping a mealworm colony recently so that I wouldn’t need to buy mealworms for my frog (it was really more of a practical decision than an interest in having a colony, but mealworms are pretty cool nonetheless)

I’ve been considering getting a mantis and/or some rhinoceros beetles, but I’m not really sure where I would be able to get the materials required to set up terrarium for them