After seeing the more comedic interpretation of the Mouse King in Drosselmeyer's flashback, the story would imply this wacky nature would continue into the current story. When Clara's kitten wanders underneath a tablecloth, it quickly backs away as a closeup of a gleaming sword cuts through, revealing a far more menacing design. The previously yellow eyes have been replaced with bloodshot reddish pink, which occasionally will flash interchanging white rings. Hinting that his Revenge has driven the previously brutish, but silly Mouse King into a vengeance-crazed lunatic that hasn't slept since his tail was ruined. And while he acts very over-the-top, his danger and capacity for violence is very much present.
And to make things worse, it has the additional twist of a dying Mouse King suddenly appearing one last time at the Land of the Dolls, while everything is shutting down, to try and kill Clara, though if it's just to spite the Nutcracker or if he's losing his senses and can't tell she's not the Nutcracker is anyone's guess - his crazy eyes strongly suggest the latter. All while everyone is unable to help. For such a mostly, light-hearted film, this finale is surprisingly dark
One other thing to note when the Mouse Queen comes to Princess Perlipat's bed-chamber, as she chants her spell, her voice getsa demonic reverb as she chants the spell and as that happens, her claws in the shadows look very disturbing around the sleeping girl.
The Mouse Queen's death can be a bit disturbing, especially since we can see her corpse flattened underneath a large pillar when the pillar fell on top of her. And while it's not made graphic, it's heavily implied her brains are sticking out of the impact of the pillar.
" that play during this sequence only add to this. Fortunately, the ending reveals that she hadn’t lost the Nutcracker after all.