Resident Evil 0 Walkthrough, Cheats, and Codes

Your guide to helping Rebecca and Billy survive

The 2002 remake of Resident Evil and its prequel, Resident Evil Zero, have been remastered and re-released as the Resident Evil Origins Collection. This walkthrough for Resident Evil 0 and Resident Evil 2002 covers all unlockables and puzzle solutions for both nightmares.

Information in this article applies to the HD remasters of Resident Evil and Resident Evil Zero for PS4, Xbox One, Switch, and PC.

Resident Evil 0 Unlockables

Beat the game under certain conditions to unlock extra modes, weapons, and costumes.

Unlockable How to Unlock
Leech Hunter Mode Beat the game.
Wesker Mode Beat the game.
Once Again (New game +) Beat the game.
Sub-Machine Gun Beat the game in under 5 hours.
Infinite Rocket Launcher Beat the game under 3.5 hours.
Rebecca's Team Wesker costume Beat Wesker mode.
Sub-machine ammo Achieve Rank E in Leech Hunter Mode.
Infinite Pistol ammo Achieve Rank D in Leech Hunter Mode.
Infinite Hunting Rifle ammo Achieve Rank C in Leech Hunter Mode.
Start With Magnum Achieve Rank B in Leech Hunter Mode.
Infinite ammo for all weapons Achieve Rank A in Leech Hunter Mode.

More costumes, including unlockable costumes from the original version of the game, are available as DLC.

Resident Evil 0 Puzzle Solutions Guide

Carefully explore your surroundings to find clues for solving puzzles, or use the guide below:

Puzzle Solution
Broken Clock Puzzle Find the Iron Needle and use it on the clock, then set the time to 8:15.
Piano Room Puzzle Have Billy play the piano to open the secret door, then switch to Rebecca and grab the battery. After the door closes behind her, have Billy play the piano again.
Duralumin case combination 385
Fountain Circle Puzzle Light the statues in this order: Deer, Wolf, Horse, Lion, Snake, Eagle.
Cable Car Combination Lock 4863

Train Brake Puzzle Solutions

You must determine which combination of 10 numbers adds up to a specified target number. For the first puzzle, there are three possible numbers and three possible solutions.

  • 36: 3 + 3 + 3 + 3 + 3 + 3 + 3 + 3 + 3 + 9
  • 67: 7 + 7 + 7 + 7 + 7 + 7 + 7 + 7 + 7 + 4
  • 81: 8 + 8 + 8 + 8 + 8 + 8 + 8 + 8 + 8 + 9

The second puzzle also has three numbers and three solutions:

  • 42: 4 + 4 + 4 + 4 + 4 + 4 + 4 + 4 + 4 + 6
  • 53: 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 + 8
  • 67: 7 + 7 + 7 + 7 + 7 + 7 + 7 + 7 + 7 + 4

Resident Evil 0 HD Achievements

Most achievements in RE 0 are secret. You can technically get them all in one run, but you'll probably have to play through the game multiple times.

Achievement How to Unlock
20/20 Vision Kill 50 enemies with the Death Stare at full charge.
A Weird Interest in Leeches Beat Leech Hunter with rank A.
Allergic to First Aid Spray Beat the game without using a First-Aid Spray.
Alley-oop! Shoot down a Hunter or an Eliminator while they are jumping.
Apprentice of Unlocking Obtain and use all keys.
Burned Alive Kill an enemy by burning them.
Calm the Zombie Nerves Play the piano as Rebecca.
Centurion Disciplinarian Defeat Centurion.
Custom to Bust 'Em Create a Custom Handgun.
Dead, Dead, Deadski Defeat a zombie by stomping on its head.
Die, Devil Bird! Kill the Infected Bat.
Distracted From the Hunt Kill all enemies in Leech Hunter.
Factory Complete Complete the factory.
Fashion Plate Change into a costume.
Fileophile Read all files.
Find Time to Combine Combine every type of herb with each other.
From Zero to Hero Finish the game on Hard difficulty.
Green is the Color Use a Green Chemical.
Guns Are Too Quick Kill an enemy with a knife.
Here I Come to Save the Day Attack an enemy to save your partner.
Hey, Queenie! Feast on this! Defeat Queen Leech.
How 'Bout a Light, Bud? Defeat Mimicry Marcus with a Molotov Cocktail or a Napalm Grenade.
I Could Shoot, You Know Obtain all weapons.
I Have the Touch Defeat Mimicry Marcus for the first time using only a knife.
I'm a Medic, Not a Bodybuilder Try to push something heavy with Rebecca.
Laboratory Complete Complete the laboratory.
Leech-Shaped Hole in my Heart Finish Leech Hunter with rank E or above.
Misdirected Hostility Destroy a zombie's legs.
On Leather Wings Get picked up by the Infected Bat.
Proto Tyrant Down Fight off the Proto Tyrant.
Proto Tyrant Down Again Defeat the Proto Tyrant.
S is for S.T.A.R.S. Beat the game with rank S.
Save Your Prayers Finish the game without saving.
Sit, Boy, Sit! Good Dog Break free of a Cerberus while they pin you down.
Taking the Sting Out Defeat Stinger.
That's Officer Chambers to You Defeat all bosses except Centurion using Rebecca.
This is How You Recycle Create a Molotov Cocktail.
This is Serious Business Beat the game without using a recovery item (including Green Chemicals).
Train Complete Complete the train.
Training Facility Complete Complete the training facility.
Treatment Plant Complete Complete the treatment plant.
Trying Out New Things Play Leech Hunter.
Wanna Go for a Ride? Earn all trophies.
Welcome to Team Wesker Put on the Team Wesker costume.
Who Needs Partners? Collect all of only one color of Leech Charms.
Who's Got the Herb? Beat the game without combining herbs.
Winged Spawn of Satan Defeat 16 bats in the church.
Zero In Kill an enemy with a critical-hit head shot.

Resident Evil 2002 Unlockables

Complete the game with each character multiple times to unlock extra modes, weapons, and costumes.

Unlockable How to Unlock
Once Again (New game +) Beat the game.
Alternate Outfit for Jill Beat the game as Jill.
Alternate Outfit for Chris Beat the game as Chris.
Alternate Outfit for Rebecca Beat the game as Chris.
Code Veronica Outfit for Chris Beat the game twice as Chris.
Nemesis Outfit for Jill Beat the game twice as Jill.
Infinite Samurai Edge Beat the game on Normal or Hard difficulty in under 5 hours.
Rocket Launcher Beat the game on Normal or Hard difficulty in under 3 hours.
Real Survivor (Hard mode) Beat the game on Normal difficulty.
One Dangerous Zombie Mode Beat the game with both Chris and Jill on Normal or Hard on the same save file.
Invisible Enemy Mode Beat the game on Hard difficulty.

Some unlockables appear in the item box in Once Again mode.

How to Save Jill/Chris

To save Jill as Chris, or to save Chris as Jill, you must find three MO Disks and use them on the disk terminals in the Underground Laboratory. You'll then receive a code to unlock the cell where either character is being held prisoner.

How to Save Rebecca

After using the Emblem Key in the mansion, you'll hear Rebecca scream. Run to the room where you picked up the dog whistle earlier and defeat the Hunter before it kills her. You must also protect her during the final boss fight.

How to Save Barry

Give Barry his gun when he asks for it. You must also protect him during the final boss fight.

Resident Evil Tofu Easter Egg

Enter MOLE as a password in the computer in the lab at the end to see an Easter egg from Resident Evil 2.

Resident Evil HD Achievements

Earning every achievement in Resident Evil HD requires you to complete all extra modes. You'll also have to beat the game with just the knife and without saving.

Achievement How to Unlock
Alpha Team’s Finest Beat the game with Jill.
An End to a Poor Girl’s Misery Defeat Lisa Trevor as Chris.
Bravo, Rebecca Save Chris as Rebecca.
Break Out the Marshmallows! Burn two zombies at once.
CQC FTW Beat the game using only the knife (can't use the lighter, defensive items, or stomp on zombie heads).
Deep Sixed Defeat Mother Neptune.
Delaying the Inevitable Save Richard with the serum.
Don’t Stop Running Beat the game in three hours.
Every Man for Himself Beat the game as Chris without saving anyone.
Every Nook and Cranny Visit every part of every map.
Every Woman for Herself Beat the game as Jill without saving anyone.
First Kills Are Special Kill a zombie.
Get Used To It Die for the first time.
Ghost of a Chance Beat Invisible Enemy Mode.
Giant Snake Got Nothin’ Beat the giant snake as Jill.
Grave Digger Beat a Crimson Head as Jill.
Herbicide Kill Plant 42 as Chris.
I’m a Member of S.T.A.R.S. Beat the game as Jill and save Chris and Barry.
Ink is for Squids Beat the game without saving.
Like Taking Candy from a Baby Beat the game on Very Easy difficulty or higher.
Not in the Mood to Die Beat the game on Easy difficulty or higher.
Not Just Any Object Obtain the Stone and Metal Object as Chris.
Not Taking Any Chances Incinerate a zombie.
Not Waiting to Exhale Survive your first encounter with the giant snake.
Oh, the Horror Beat the game on Hard difficulty or higher.
Passion for Fashion Obtain all costumes.
Platinum Splattin’ ‘Em! Earn every trophy.
Racing and Pacing Beat the game in five hours or less.
Seeing Red Defeat a Crimson Head.
Sorry About the Wait Save Chris as Jill.
Sorry I Made You Wait Save Jill as Chris.
Spider Sense Defeat Black Tiger.
Starsenal Obtain all weapons and ammo.
Take that, Zombies! Beat the game on Normal difficulty or higher.
That Was Nice of You Save Rebecca from a Hunter.
The Key Master Obtain the Helmet Key as Jill.
The Nightmare Ends Beat the game and save Rebecca and Jill as Chris.
The Survival Horror Beat the game in Real Survival mode.
Trust Him Save Barry from Lisa Trevor.
We’re in This Together Beat the game with Jill and Chris.
What a Great Guy  Save Jill as Barry.
Where the Magic Happens Break into the laboratory as Jill.
Who’s the Hunter Now? Kill a Hunter.
Written Word is Dead Obtain the “Last Book Vol. 2" as Chris.
You da Man, Chris Beat the game as Chris.