Fritz is probably the most awesome character in the movie. He takes on an army of polyps using starfish and a mermaid skull as weapons, and saves Marina multiple times.
The sisters must have braved the sea witch's lair - one that's filled with scores, if not hundreds of mermaid skeletons - to save their sister.
Scuttle's Pep-Talk Song to Ariel when she collapses from her attempt at walking. He rallies all the birds to motivate her, and soon she's dancing with them.
Whereas Eric saves the day, it's quite different in the stage/Broadway musical. Without her magic shell that she was given by her father, Poseidon, Ursula will die without it. In the climax, Ariel smashes the shell, destroying Ursula and saving the day.
During the 30th anniversary live performance in 2019, Queen Latifah burned her hand during "Poor Unfortunate Souls," laying it on a piece of the set still hot from the pyrotechnics. But after a brief yelp of pain, she went right back into the song without missing a beat, doing full justice to one of Disney's most beloved villain songs.