I've got a few of the small agave's and succulents that have survived several sets of kittens we were boarding. They always chew on the Agave Victoria reginae for some reason. I finally took it out of the ground and put it in a small rock planter hoping I could protect it. So far it looks a little better, it's the one at the bottom of the first pic.
The bright red is C. bivittatus 'Ruby'. I have several of them and this one has the brightest color, probably because it has been in almost full sun. I've now moved the others out of partial shade to see if they get more red.
The rounded one top left is Mammilaria uberiformis according to the tag. It's grown a bit over the last year in spite of being knocked out of its plantar several times. At least they don't seem to chew on it.
I've lost the tag for this one, I'm still looking for it. It has been uprooted several times and I'm just hoping it doesn't die. Don't worry about all the water in the plantar, I had just rescued it again and put it in that plantar. The water will drain out quickly.
These are a couple of Haworthias.
Haworthia gracilis:
Haworthia cymbiformis:
and the agave native here in the Yucatán,
Manfreda petskinil: