thinking abt designs for the mythosaur and shriek hawk, because the canon mythosaur does in no way resemble a semiaquatic jungle creature, and the canon "shriek hawk" appears to either be some sort of dino-planet mutant population or somehow crossed with nevarro dragons, especially since it doesn't even match the silhouette of the vizsla shriek hawk- either way, the shriek hawk equivalent of those super squashed french bulldogs.
so. starting with the mythosaur:
disclaimer: this is pulling from both legends and canon, and also from the perspective of someone whose background is in general dentistry, not paleoart reconstruction
our only existing examples of mythosaur fossils are the skull insignias and replicas: the original cracked-skull signet from boba's pauldron, the stylized signet from jaster/the haat'ade, grogu's pendant, and the one on the armorer's wall in the nevarro forge.
this is further complicated by mythosaurs being sexually dimorphic at a skeletal level as well as the iconic sigil being apparently based off a humanoid species that resembles a male mythosaur:
the Jaing mythosaur seems to feature the binocular eyes/eye sockets seen most clearly in the boba and jaster signets, but broader-set and straighter tusks than almost all the attributed mythosaur skulls. assuming that basic features like eye/nose placement and mandibular structure aren't dimorphic, the Forge mythosaur is probably the most accurate representation of a mythosaur skull.
the only appearance of a nearly-complete mythosaur skeleton is in the form of a defunct theme park of dubious accuracy and proportions, depicted in one issue of a comic from 1977:
this is... certainly something, to say the least. the skull part features the same monocular eye placement (correlates with the Forge mythosaur), oddly-placed nose horns (and no nostrils, and also weird nose-abs), remarkably no tusks, some sort of unicorn-ceratopsid horn crest.
The vehicles for scale are unidentified transport barges, but they seem to be about a foot taller than leia in the back, so approximately 6ft? judging from the transport in the eye-door, the orbital socket is approximately 48 ft across.
in comparison, our other data points in terms of size demonstrate 1) at least one mythosaur (the Living Waters mythosaur) has a head at least twice as tall as din, so approximately 12ft of visible head in comparison to the 48ft-eye of the Theme Park mythosaur. 2) some number of mythosaurs were large enough and of a reasonable shape to be ridden. 3) mythosaurs generally have some large bones of a size appropriate for mythosaur axes, but most likely not so large that the entire axe could be carved from one bone (given the segmented axe shape). 4) all(?) mythosaurs have a sternum bone of a size reasonable for the carving of the mask of mandalore and presumably of a shape reminiscent of the bes'karta.
the Living Waters mythosaur also provides some valuable detail on its face: it appears to be a large reptilian with rough skin of a muted color, seemingly demonstrating the elongated facial structure and the separate tusks (so not a hippo skull situation).
it seems quite odd that the Theme Park mythosaur depiction would leave out the tusks, so given that the Jaing mythosaur resembles a specifically male mythosaur, i'll assume the female mythosaur has the unicorn-ceratopsid crest instead. i'm also going to assume the nose horns are a iguanodon situation, so i've moved them to points of the cheek ridge like ceratopsid cheek points.
looking at these examples, the weirdest thing that seems to stand out is the oddly vertical jaw- where does the mandible attach? how does it eat?? does it actually bite offensively if it has to smush its whole face up to where it's biting?? what sort of range of motion does it have?? the Jaing mythosaur/Jaing species and the Theme Park mythosaur both have more horizontal heads that would better facilitate eating in a hand-less predatory animal; however, the Living Waters mythosaur does have that weird vertical jaw (unless its mouth goes at a 90 degree angle from the rest of its face, like a goblin shark). then again, we can't rule out that the Living Waters mythosaur is just a weird individual with some facial deformity causing the impractical verticality.
that said, why does it have rodent teeth. where are the rest of its teeth. why does it have a huge gap in the side of its face.
i tried putting skin over it and now it looks like a sock puppet.
time to try again with a more forward-angled maxilla, instead of just continuing the angle of the upper face.
i... don't know if this is worse. it looks like some sort of horrible sauropod-rat. well, at least the canon version looks at least as unwieldy as this :/
possible solution for the vertical face: maybe it rotates like how gorilla heads stay facing forward when they're knuckle walking or bipedally walking? but like a weird reptilian version? but then their teeth would be horizontal :///
alright. take three, this time with a more humanoid vertical jaw.
it now looks like it ran facefirst into a brick wall. unsure if this is an aesthetic improvement from the sauropod rat, but it seems even less functional in terms of range of motion and durability. however, the occlusion is a bit better in the resting state?
looking at it again, how does it even fight. the tusks would seem like the obvious answer but they seem too close to the face? and the teeth are huge but they're weird flat skinny incisors that are way too vertical to be of use without smushing the entire face up against the prey.
not to mention these are supposed to be jungle creatures?? judging from the Living Waters mythosaur i'm going to assume they're some sort of jungle river creature-
-ARE THEY BALEEN FILTER FEEDERS
apparently baleen is a non-fossilizing soft tissue, which would explain why the Theme Park mythosaur doesn't seem to have any functional teeth, and those weird skinny incisors can either be some sort of baleen-like tissue replicated as "teeth" in the classic "mythosaur skull" (especially if the Jaing species and associated Jaing mythosaur actually did have teeth), or something like split rostrum whales.
that would also explain how such a huge creature supports large global populations
well, this still needs some work, but it definitely looks better than sock puppet mythosaur... except no, the nostrils probably wouldn't work if the baleen attach to the front of the skull.
going back to look at the front view, the Forge mythosaur seems to have some indentations between its eyes, kind of like where rancor nostrils are, that look similar to trunk attachment points. except the actual nostrils are lower on the Living Waters mythosaur.
going back to rodent teeth
THATS WHAT HAS WEIRD LONG SKINNY INCISORS
irl, beavers have iron deposits in their enamel to prevent wear/stress during tree-gnawing activity. what if. beaver mythosaur. with BESKAR INFUSED TEETH
mandalore also has massive veshok forests - hardwood trees remarkable for their sturdiness. so it makes sense that something would make use of those giant veshok trees!
BEAVER MYTHOSAURS WITH BESKAR TEETH THAT GNAW VESHOK TREES
BEAVER MYTHOSAUR BUILDING A DAM UNDER THE LIVING WATERS
beavers eat mostly wood and assorted vegetation; to maintain both the herbivore teeth and the reptilian appearance i've added marine iguana features to the mix. (conveniently, iguanas' parietal eye nicely explains the indentation in the middle of the Forge mythosaur's forehead)
it. it looks so dumb but a little more in a Weird Animal way and not a sad deflated sock puppet
...now on to the rest of the body (essentially, it's a 60-ft-long marine iguana with beskar teeth and beaver behavior) :
their reputation as fierce beasts/honorable foes can likely be attributed to Large Herbivore. it's a mandalorian beaver-iguana-moose. with beskar teeth.