an alien world calls for some alien animals. or “animals”. whatever they are. no reason it has to fit into our constructed plant/animal/fungus/etc categories.
some winners, some not so much. some of them have showed up already, like the weird jellyfish plant thing and the spore vines. the varieties of horses will probably show up again. the others we will have to see. trying to not let myself be limited by earth life, it is quite difficult. there is a reason why people often default to what they know.