This may have been asked before but are the silhouetted enemies going to be given character portraits or no? This is just me guessing but most of the creatures that haven't been given sprites can be described as feral in one way or another, like actual feral wolves or questionably feral/ primitive types like the troglodytes.
The list of the "no sprite/silhouette sprites" largely includes "ferals" such as wolves, cave crawlers, raptors, rats, raptor riders, and the elk that the satyr can summon.
It also includes possible exceptions to being feral but are at least semi primitive if not still actually like the murcads, ragroaches, and troglodytes, and a few creatures with indifferent reputations.
There's also the indifferent to reputation creatures, which other than the slimes don't have sprites. This list includes the tar beings, the hornets, the ghouls, the skeleton(which I really wish could be boned like creatures outside of this tier) and the bat and crab which may or may not count as they do have a reputation(-20 and -40) but it just cant be changed.
There's also the enemies who are women but they clearly are being worked in (see; nymph, Victoria, and rose) slowly as most people are here for the men.
The majority of them have questionable consent due to them being feral or seemingly so which made me wonder if they're being actively excluded from getting sprites or they just haven't been gotten to them yet. This is accented by the fact that the wolf and rat counterparts, like the werewolf and the ratkin, have sprites while they still don't. That specific fact made me wonder if they're different from the other enemies that have been given sprites to stay away from actually including nsfw feral artwork as that's at least somewhat controversial online even in the furry world.