Bonus items
There are two bonus items per scenario. Get an "A" or better rank under the Normal difficulty setting to unlock the first item. Get an "S" rank on the hard difficulty setting to unlock the second item (and first item if not already unlocked).
Battery: Dark Legacy 2 with an "S" rank
Blue/Green Leech Charm: Train Derailment 3 with an "A" rank
Blue/Red/Green Chemical: Umbrella's End 2 with an "A" rank
Blue/Red/Yellow Gemstone: Rebirth 2 with an "A" rank
Book of Wisdom/Future Compass: Raccoon's Destruction 1 with an "S" rank
Briefcase: Train Derailment 1 with an "S" rank
Chronos Key: Raccoon's Destruction 3 with an "S" rank
Clark/Gail X-Ray: Rebirth 1 with an "A" rank
Crystal/Obsidian/Amber Ball: Raccoon's Destruction 3 with an "A" rank
Cylinder Shaft: Nightmare 1 with an "A" rank
Death Mask: Rebirth 2 with an "S" rank
Eagle/Serpent/Jaguar Stone: Fourth Survivor with an "S" rank
Emblem/Gold Emblem: Nightmare 2 with an "S" rank
Film A/B/C/D: Umbrella's End 1 with an "S" rank
Fire/Water Key: Beginning 2 with an "A" rank
Fuel Canteen: Mansion Incident 3 with an "S" rank
Great Eagle/Wolf Medal: Mansion Incident 1 on the Hard difficulty with an "S" rank
G-Virus: Fourth Survivor with an "A" rank
Hex Crank: Nightmare 1 with an "S" rank
Ink Ribbon: Umbrella's End 3 with an "S" rank
Joint N/S Plug: Raccoon's Destruction 2 with an "A" rank
King/Knight/Bishop/Rook Plug: Dark Legacy 1 with an "A" rank
Last Book, Vol. 1/2: Nightmare 2 with an "A" rank
Lighter/Lockpick: Mansion Incident 1 on the Normal difficulty with an "A" rank
Lighter Fluid: Raccoon's Destruction 2 with an "S" rank
Medium Base: Dark Legacy 1 with an "S" rank
Microfilm A/B: Beginning 2 with an "S" rank
Mixing Set: Train Derailment 1 with an "A" rank
MO Disk: Mansion Incident 3 with an "A" rank
Motherboard: Beginning 1 with an "A" rank
Picture (Ada and John): Death's Door with an "A" rank
Plastic Bomb/Detonator: Umbrella's End 1 with an "A" rank
Relief of Discipline/Obedience/Unity: Train Derailment 2 with an "S" rank
S.T.A.R.S. Card (Brad): Death's Door with an "S" rank
S.T.A.R.S. Card (Jill): Raccoon's Destruction 1 with an "A" rank
Slide Cartridge: Rebirth 1 with an "S" rank
Spade/Diamond/Club/Heart Key: Dark Legacy 2 with an "A" rank
Square Crank: Umbrella's End 2 with an "S" rank
Statue of Good/Evil: Train Derailment 2 with an "A" rank
Sterilizing Agent: Train Derailment 3 with an "S" rank
Sun/Star/Moon Crest: Mansion Incident 2 with an "A" rank
V-Jolt: Mansion Incident 2 with an "S" rank
Vaccine: Umbrella's End 3 with an "A" rank
Valve Handle: Beginning 1 with an "S" rank