Which Pixar film introduced the character Mike Wazowski before Monsters University?

Monsters, Inc. introduced the character Mike Wazowski before the prequel Monsters University.

Mike is one of the central characters in Monsters, Inc., where he works with Sulley at the factory and helps manage scare-floor assignments. His one-eyed design, quick speech, and comic confidence make him immediately recognizable. Billy Crystal provides Mike’s original English voice.

Monsters University, released in 2013, explores Mike and Sulley’s earlier student years. Because it is a prequel, audiences sometimes remember it as Mike’s first appearance. Chronologically it comes first in the characters’ lives, but Monsters, Inc. was produced and released first and is the film that introduced him to audiences.

The earlier Pixar films Toy Story 2 and A Bug’s Life feature different casts and settings. Finding Nemo was released after Monsters, Inc. and also does not introduce Mike.