Uh, maybe because monster death animations make up a small part of the training material (ie. gameplay) so the model has not learned to reproduce them very well?
There cannot be "video compression artifacts" because it hasn’t even seen any compressed video during training, as far as I can see.
Seriously, how is this even a discussion? The article is clear that the novel thing is that this is real-time frame generation conditioned on the previous frame(s) AND player actions. Just generating video would be nothing new.
In a sense, poorly reproducing rare content is a form of compression artifact. Ie, since this content occurs rarely in the training set, it will have less impact on the gradients and thus less impact on the final form of the model. Roughly speaking, the model is allocating fewer bits to this content, by storing less information about this content in its parameters, compared to content which it sees more often during training. I think this isn't too different from certain aspects of images, videos, music, etc., being distorted in different ways based on how a particular codec allocates its available bits.
I simply cannot take seriously anyone who exclaims that monster death animations are a minor part of Doom. It's literally a game about slaying demons. Gameplay consists almost entirely of explosions and gore, killing monsters IS THE GAME, if you can't even get that correct then what nonsense are we even looking at.
There cannot be "video compression artifacts" because it hasn’t even seen any compressed video during training, as far as I can see.
Seriously, how is this even a discussion? The article is clear that the novel thing is that this is real-time frame generation conditioned on the previous frame(s) AND player actions. Just generating video would be nothing new.