I always thought veggietales used some sort of projected image for the mouths, In like 2017 I was trying to figure out how the models were rigged, I spent so long on it, booleans didn't look right and if you tried subdiv mouths the model would stretch in weird ways. turns out I was right I was looking at it earlier today and noticed different pixel density on the mouth, so I looked it up and yeah they used image projection alpha and like some weird thing that created a normal out of it

recently I've been using my ray camera rasterizer for a lot of stuff so I'm gonna try to see if I can use closures in blender 5.0 to get the color or something and actually use it like an alpha map, big developments in the veggietales landscape because it was the thing that made me interested in 90's cg in the first place