#48 VenonatFirst Appearance: Tracey has it in his debut episode (Episode 84, "The Lost Lapras")
Venonat is a bug-type Pokemon used by Tracey. Its insect eyes act like a radar, finding anyone or anything Tracey needs to find (like the Lapras that Jessie and James stole). In Episode 32, "The Ninja Poke-Showdown," Koga, the Fushia City Gym Leader, uses a very experienced Venonat which evolves into Venomoth. But Ash beats it easily with his Charmander.
#183 MarillFirst Appearance: It is already caught when Tracey first uses it (Episode 87, "The Crystal Onix")
Marill, a water-type mouse pokemon, is the third of the new Pokemon from Gold and Silver (after the Ho-oh that flew over the rainbow in Episode 1, "Pokemon, I Choose You!" and Misty's Togepi). Marill has super-strong hearing, which is first used to find the Crystal Onix. Marill makes its debut in the short "Pikachu's Vacation" as one of Pikachu and Togepi's vacation buddies. Its round tail acts like a rubber ball, floating on the top so that Tracey can keep track of it when it dives underwater.
#123: ScytherFirst Appearance: Episode 97 ("Tracey Gets Bugged")
Scyther is a green mantis-Pokemon who is lynched because it's not the gang leader anymore. Tracey nurses it back to health, and it soon joins him. Scyther is stubborn and never gives up, putting its own life in danger just to win a battle. Scyther is seen earlier in Episode 42 ("Showdown in Dark City") as one of the rival gyms' head Pokemon. Seeing red made it go beserk, and the rivalry between the two gyms was settled.