Resident Evil 4 HD Cheats - Xbox 360

Cheat Mode
On the character select screen for The Mercenaries hold the following buttons while choosing the noted characters:

Hold [RB] and press [A] - Ada with Assignment Ada outfit.
Hold [RB] and press [A] - Leon with RPD outfit (RE2).
Hold [Y] and press [A] - Ada with Separate Ways outfit.
Hold [Y] and press [A] - Leon with jacket.
Hold [Y] + [RB] then press [A] - Leon with Gangster outfit.

Achievements
Complete each achievement to receive the allotted gamerscore:

A Rock and a Hard Place (50) - Outmaneuver the rampaging beast, El Gigante.
A Bloodline Severed (50) - Defeat the village chief in battle.
A Heart of Steel (150) - Clear the game on the highest difficulty.
A Terrifying Assassin (150) - Turn the tables on Verdugo, the right hand of Salazar.
Do Not Shoot the Water! (50) - Summon the master of the lake. Don't rock the boat.
The Castellan Falls (50) - Defeat Salazar, and make your escape from the castle.
The S Stands for Stylish!! (100) - Acquire all of the costumes in the game.
It Begins With a Ring (50) - Ring the mysterious bell. What happens after that, is up to you.
Secure the Ballistics (50) - Rescue the president's daughter, Ashley. Afterwards, the real fun begins.
The Ties That Bind (50) - Defeat Krauser, your former partner, in battle.
We're Going Home (100) - Defeat Saddler in battle, and escape from the nightmare.
What Are They Worth? (150) - Acquire all of the bottle caps in the game.

Maximize Leon's Life Bar
This process incurs several continues, which have no bearing on the game's ending. At the first El Gigante fight, there is a Yellow Herb in the boss arena. Take this item and combine it with any of the Green Herbs in the same room and use it. This increases Leon's lifebar slightly. Now let the boss kill Leon. Since the boss' room is at a map transition (the green OPEN command is a dead giveaway), this lets you continue right at the boss fight but with Leon's life increase from your previous attempt. Repeating this process will increase Leon's lifebar to maximum prematurely. Extra Yellow Herbs found later can be given to Ashley, or sold to the merchant for money.

Unlock Mercenaries Characters
Albert Wesker - Get four stars or higher in the Waterworld.
Ada Wong - Get four stars or higher in the Village.
Jack Krauser - Get four stars or higher in the Castle.
HUNK - Get four stars or higher in the Base.

Unlock Bonuses
Alternate outfit for Leon, Ashley, Ada - Beat the game once.
Infinite Rocket Launcher - Beat the game once.
Handcannon - Obtain five stars for each level in the Mercenaries.
Professional Difficulty - Beat the game once.
P.R.L. 412 - Beat the game on Professional.
Chicago Typewriter (Main game) - Beat Seperate Ways.
Seperate Ways - Beat the game once.