Transformers: Beast Wars Transmetals 64 Codes -

Ravage and Tigatron:
Select vs. or arcade mode. Highlight Cheetor, then hold and press at the character selection screen. Then, press or to go through his colors to get to Ravage and Tigatron.

Starscream:
Select vs. or arcade mode. Highlight Waspinator, then hold and press at the character selection screen. Then, press or to go through his colors to get to Starscream.

Black Arachnia:
Select vs. or arcade mode. Highlight Tarantulas, then hold and press at the character selection screen. Then, press or to go through his colors to get to Black Arachnia.

Original Rattrap:
Successfully complete the game, including defeating Megatron X. Select vs. or arcade mode. Highlight Rattrap, then hold and press at the character selection screen. Then, press or to go through his colors to get to his original appearance.

Alternate costumes:
Select one of the following characters and press or . Optimus, Trantulas, Airazor, and other characters have a strange Blue form.

Airazor: TigerHawk look-alike
Airazor: Noctorro Look-alike
Cheetor: Young Tigertron look-alike
Megatron: Transmetal 2 Dinobot look-alike
Opimus Primal: Him with Predicon symbol (in beast mode)
Optimus Primal: Optimal Optimus
Optimus Primal: Polar Claw Look-alike
Rattrap: Odd Rattrap
Tarantulas: Cyborg Tarantulas
Tarantulas: Old Tarantulas
Terrorsuar: Old Terrorsuar (colors)
Terrorsuar: Depth Charge Look-alike
Terrorsuar: Onyx Primal Look-alike
Waspinator: Buzz Saw Look-alike
Waspinator: Insecticon look-alike

Fight Megatron X:
Successfully complete the game with Megatron with no time limit. You will have to fight Megatron X at the end.

Defeat Megatron X:
Press to keep firing your gun until you get a Energon Strike. Transform into vehicle mode. Then transform into beast mode and keep pressing rapidly until your Energon bar is filled. Get close to Megatron X. Repeat this you defeat Megatron x twice.

Metal Megatron:
Defeat Metal Megatron in arcade mode to unlock him as a playable character.