From the Gamera series we have the MOST iconic of all his foes, the mighty knife faced Guiron. Guiron is an alien monster whose main attribute is this his head is a machette hard enough to crack Gamera's shell. He can also leap farther and higher than any kaiju I know and has telekinetic shuriken lodged in his blade/snout.
Ok taking all this into account I started be checking out animals with powerful necks. Charging animals like bulls, buffalo and rhino were my first subjects of research (hence the pawing at the ground pre charge pose). Then I took a look at the Reek from Star Wars and the Kothoga from The Relic. To support that huge horn/blade my design had to have a very powerful neck, this neck needed to deliver powerful axe blows and head thrashes. Equally important was a heavily muscled and powerful body to balance the weight on the kaiju's front end. So I made this my thickest kaiju yet. His legs are also powerful but stumpy which actually fits in well with the original's context.
Since Guiron is a quadreped but like all good kaiju can stand when needed I blunted the end of his tail and make it rigid and muscular to act as a third limb for standing kinda like a kangaroo uses. In the film his shuriken are hidden beneath a membrane that just disappears when they are in use. I decided to implement a short of shuriken shooter nasal passage like structure on the blade. Guiron has one of the most durpy faces in all kaijudom with his super sleepy eyes. Couldnt have that. I went with something that gives him a more applicable field of vision and eyes inspired by my gecko turned sideways. I gave him huge rancor-like nostrils to drive his metabolic needs as such a powerhouse. Plus he can do some cool angry bull snorts now. Since the blade is part of his head I set his enormous fangs right into his armored skull instead of gums. Everything about this guy was built to say power...like a bulldog version of a kaiju. And since Im tired of scales I went with a thick elephantine hide.