This scene from LBT X is quite hilarious:
The Gang minus Littlefoot are trying to wake up Petrie by calling to his nest.
Off-screen voice (I think it's Cera): "Psst! Petrie! Petrie, wake up!"
Petrie: "Me awake!"
Followed by a soaring watermelon, which pegs Petrie

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From LBT VIII:
The Gang hears a weird noise that sounds like someone cut the cheese, and everyone looks at Cera.
Littlefoot: "What was that?"
Cera: "Don't look at me!"
From LBT III:
The scene where the bullies stop and look around some bushes for the Gang.
Nod: "Where'd they go?"
Hyp: "If I knew I wouldn't be looking!"
Nod: "Yeah!"
Mutt (looking at flower): "Yeah! Dummy!"
Flower moves as Mutt makes a WTF expression, then an angry hornet emerges. The bullies' "Aw, s***!" like reactions followed by them being chased by the hornet is hysterical

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A'ight, one last one for now

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From LBT VI:
Littlefoot is alone at his nest getting his Lone Dinosaur on.
Littlefoot: "Are you talking to me? Are you...talking to me? Then who...are you talking to? Ya sure you're feelin' up to it, friend?"
Littlefoot then snaps himself in the leg with his own tail.
Littlefoot: "Ouch!"
Grandpa then emerges as if nothing happened

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