Red Dead Revolver

Cheat mode:
Cheats are unlocked by completing Bounty Hunter challenges. They are
then available in the pause menu. Complete the indicated Bounty Hunter
levels to unlock the following cheats:

Level 1: Falling Star as a showdown char.
Level 2: Curly Shaw as a showdown char.
Level 3: Twiggy Phelps as a showdown char.
Level 5: Sheriff Bartlett as a showdown char.
Level 6: Fidgit as a showdown char.
Level 7: Professor Perry as a showdown char.
Level 8: Sissy Fess as a showdown char.
Level 9: Dig Fowler as a showdown char.
Level 11: Smitty as a showdown char.
Level 12: Natalie as a showdown char.
Level 13: Fallen Peak as a showdown stage
Level 14: Sunset Canyon as a showdown stage
Level 15: Grizzly as a showdown char.
Level 17: Sad Stars cheat
Level 18: Disable HUD cheat
Level 20: Bite the Bullet cheat
Level 21: No Distortion cheat
Level 24: Unlimited Deadeye cheat
Level 25: Golden Gun cheat
Level 27: Invincibility cheat

Unlock bounty hunter and hard mode:
Finish the game once

Unlock the Very Hard and Red Wood Revolver modes:
Finish the game in hard mode

Unlock all showdown characters and journal pages:
Purchase every item from the stores