The vast majority of Batty's dialogue. What else would you expect coming from Robin Williams?
"Oh! Gravity works!"
"Oh, Caesar, Emperor of Rome!"
"WE ARE LOCKED AND LOADED, GENTLEMEN!!! TIME TO ROCK AND ROLL!!!! YEEHAW!!!!"
"I have but one claw; but beware."
"Oh, it's Darwin's grab-bag!"
Crysta: "But just think! Humans, back in the forest!"
Batty: "Yep. There goes the neighborhood."
Crysta: "Be nice, Batty!"
Batty: "First, all these trees go. Then come your highways, then come your shopping malls and parking lots and convenience stores, and then comes- (Zak slaps him to quiet him) Price check on prune juice, Bob? Price check on prune juice?"
(Crysta's father is confused and he and a smirking Zak just shrug at each other)
"Human tales? Human's don't have tails! They have big, big bottoms that they wear with bad shorts, and they walk around going 'Hi, Helen!'"
More hammy Batty: "I'M BLIND!!(beat) "I can see! It's a miracle!!"
"See you around, Zag!"
When Zak and Pips shake hands and give the thumbs up, Pips looks at his thumb and wonders if Zak tricked him into doing an uncool gesture.
"Uh, Tony, there's a little man on the window."
This one shot after Zak kisses Crysta shows him glance downward and nearly jump out of his skin at what he sees. If you haven't seen this movie before and didn't know what was really going on, you'd believe that he was...for lack of a better term..."Just happy to see her".