I’m fiddling with a card game concept, and a very important part of it is creatures interacting with other specific kinds of creatures. This necessarily means I need to come up with lots of type names that are descriptive but vague enough to shove literally anything in them. Here’s some good examples: “bug” containing ants, shrimps, pillbugs, bees, and literally anything that could be called a creepy crawly; “fish” containing everything from salmon to sharks to eels to octopi; “trees” containing all the stuff you are thinking of as well as those precambrian 6-foot fungi pillars; and “cats” including housecats, big cats, cheetah, and carcals.
And that’s everything I can think of that would be useful. You see my problem? I know there are other casual-usage words for big categories of critters, but my grasp of the Enlgish language is fickle and leaves me whenever it is most inconvenient. If there is a list I could work from, that would be very helpful. Otherwise, volunteer as many words as you think would be useful.
And that’s the only word you need, right there.
“Critter” being a variant of “creature”, which OP also uses. They seem to want something coarse-grained but not that coarse.