Giant Rat No. 9,375

Giant Rat #9,375 was the leader of the Rats at the beginning of both Rat Movie videos. In both timelines, however, he is killed. Giant Rat #9,375 was the one who decided to hunt for the Mayan Treasure (Timeline A) and go to Michael's birthday party (Timeline B). Giant Rat #9,375's favourite movie is Frozen.

Timeline A
The first thing we see at the beginning of Rat Movie: Mystery of the Mayan Treasure is Giant Rat #9,375 leading the infamous Rat Chant. He proclaims, "I'm the giant rat that makes all of the rules!". #9,375 is next seen when he enters the cave where the Mayan Treasure is held and kills Dick Dastardly, only to be struck down by Sammy the Scientist.

Timeline B
Giant Rat #9,375 is only seen once throughout Rat Movie 2: The Movie, when he becomes stuck in a toilet on the way to Michael's birthday party. He is then flushed down the toilet by his second in command (who becomes Giant Rat #9,376), presumably to his death.