Tracey Sketchit.

Tracey is the franchise's quietest mainline companion, joining mid-Orange Islands when Brock stays behind on Valencia Island with Professor Ivy (a plot beat the writers immediately regretted, evidenced by Brock's refusal to discuss Ivy in subsequent episodes). Tracey's career goal is Pokémon Watching: sketching wild Pokémon in their natural habitats. He idolizes Professor Samuel Oak the way a graduate student idolizes a thesis advisor.

The Orange Islands arc gives him a full tour with Ash and Misty across the archipelago; his observational skill is a useful narrative excuse for naturalistic episodes that focus on Pokémon behavior over battles. Catches Marill (whose pop-culture popularity briefly rivaled Pikachu's in 1999), Venonat (later evolves to Venomoth in Pokémon Chronicles), and Scyther. Once Ash returns to Kanto, Tracey takes the open lab-assistant position at Professor Oak's; he stays in that role permanently, appearing in Chronicles and occasional Kanto-set episodes thereafter.