Oops - just saw this!
See my reply below 😉

Each scene is hard animated (I guess).
But I created functions for a simple animation system (table of SPR frames, keyed off a "string" name), with frame speed, etc.
Then also created simple 'tweening, jump & messaging functions - and that those make up the most of it.

The Coroutines allow me to script the animations very much like a movie script:

move_to(self,self.x+30,self.y,.25)
self:set_anim("idle")
wait(50)
self:set_anim("cheer")
self:set_message("a BIRTHDAY CAKE!",self.x-20,self.y-20,12)
wait(100)
self:set_message("a BIRTHDAY CAKE!\nhOW NICE.",self.x-20,self.y-20,12)
wait(100)
self:set_anim("idle")
self:set_message("i THINK I'LL GO BLOW\nOUT THE CANDLES.",self.x-20,self.y-20,12)
wait(150)
self:clear_message()
self:set_anim("walk")
move_to(self,self.x+5,self.y,.25)
baby_cake:set_message("       /\nhELP, MOMMY!",baby_cake.x-40,baby_cake.y+25,14)
self:set_anim("walk")
move_to(self,self.x+20,self.y,.25)
move_to(momma_cake,0,momma_cake.y,4)
baby_cake:clear_message()
self.flipx = true
self:set_anim("idle")
momma_cake:set_message("sTOP RIGHT THERE,\nBUSTER!\n  /",momma_cake.x+20,momma_cake.y-20,14)

etc. etc. 🤓

Wow I had no idea pico 8 had these..!! I'll have to give em a shot!