Satisfying the following requirements will unlock additional characters and costumes in Raid Mode.

Unlockable	How to unlock
Chris Redfield (Sailor)	Inflict 100,000 damage in a single shot in Raid Mode.
Chris Redfield (Wetsuit)	Reach Level 30 in Raid Mode.
Clive R. O'Brian	Reach Level 20 in Raid Mode.
HUNK	Obtain an S rank on every Raid Mode stage on "Abyss" difficulty.
Jack Norman	Clear every Raid Mode stage on "Abyss" difficulty.
Jessica Sherawat (Terragrigia)	Reach Level 40 in Raid Mode.
Jessica Sherawat (Wetsuit)	Clear every Raid Mode stage on "Trench" difficulty.
Jessica Sherwat (Snow)	Clear every Raid Mode stage on "Chasm" difficulty.
Jill Valentine (Beach)	Obtain a super-rare weapon.
Jill Valentine (Pirate)	Complete the "Ghost Ship" bonus stage.
Keith Lumley (Casual)	Obtain an S rank on every Raid Mode stage on "Chasm" difficulty.
Keith Lumley (Ninja)	Reach Level 50 in Raid Mode.
Keith Lumley (Snow)	Clear Episodes 4-6 in Campaign Mode.
Morgan Lansdale	Obtain an S rank on every Raid Mode stage on "Trench" difficulty.
Parker Luciani (Beach)	Earn 10 total bonuses in Raid Mode.
Parker Luciani (Terragrigia)	Defeat 10,000 enemies in Raid Mode.
Quint Cetcham (Casual)	Obtain every super-rare weapon.
Quint Cetcham (Snow)	Reach Level 5 in Raid Mode.
Rachael Foley	Acquire the "Trinity" bonus for the first time.
Raymond Vester	Reach Level 10 in Raid Mode.