These are in no particular order

Mabel: *braces caught in the screen door* BRACES!!!! BRACES CAUGHT IN THE SCREEN DOOR!!! SOMEONE DICTATE MY WILL!!! IM GIVING IT ALL TO WADDLES!!
-Soos and the Real Girl

Gideon: I wouldn’t a hair in your itty bitty head! If you agree to be my queen!
Mabel: we live in a democracy!!
-Little Dipper

Stan: people don’t roll around in their own filth!
Mabel: and we’re the lesser for it! Maybe WE’RE the ones who should be put outside! Huh? Huh? Think about it!
-Land Before Swine

Mabel: Grunkle Stan, karaoke isn’t about sounding good. It’s about sounding terrible TOGETHER!
-Scary-oke

Mabel: there’s a wizard in this closet isn’t there?! Isn’t there?!
Dipper: fine! Open it!
Mabel: *opens the door and looks inside the empty closet* an invisible wizard?! REALLY Dipper?
-Little Dipper

Dipper: there it is Mabel, our ticket to any moment in history
Mabel: let’s go get two dodos and force them to make out!
-The Time Traveler’s Pig

Mabel: *banging on the window of the diner* DIPPER HIII!! ITS ME MABEL!! IM TALKING TO YOU THROUGH THE GLASS!! THIS IS MY VOICE!!
-Dipper vs. Manliness

Mabel: GRAPPLING HOOK!
-Tourist Trapped and Gideon Rises

Mabel: Soos! Your grandma is so adorable! And her skin is old lady soft! *rubs Soos’s grandma’s skin and makes noises that I can’t put into words*
-Gideon Rises

Mabel: you leave our uncles brain alone your isosceles monster!
-Dreamscaperers