Orb I
Orb II
Orb of Agamotto
Orbucen
Orcale II

Member of: S.H.E.

Ord
Order (CtrEarth2)

Alternate version of: Master Order
Member of: Young Allies II
Universe/Dimension/Timeline: Counter-Earth II

Order I
Order II
Organizer
Ori
Origin
Origins Corporation

Creator(s) of: Aberration, Axon, Morass
Founded by: Norman Virgil Osborn
Leader of: General John Ryker
Subgroup(s): Gamma Corps Black

Orion
Orka
Orphan-Maker
Orrgo the Unconquerable
Ortlinda

Gender: ♀
Member of: Valkyrior

Elizabeth Osborn
Harold Theopolis Osborn
Harold Theopolis Osborn (Earth MiniM)
Harold Theopolis Osborn (M2)

(Harry)
Gender: ♂
Alternate version of: Harold Theopolis Osborn
Child(ren): Norman Osborn, Jr.
Universe/Dimension/Timeline: Earth M2 (Earth-982)

Harold Theopolis Osborn (Ultimate)
Norman Virgil Osborn
Norman Osborn, Jr.
Osiris
Other-Earth
Ouranus

(Uranos)
Gender: ♂
Individual of: Greek Pantheon
Parent(s): Gaea

Features
Official Handbook of the Marvel Universe A to Z Update 2.FT

Outback

Frederick Myers
Gender: ♂
Alias of: Boomerang
Member of: Heavy Hitters

Outcast

Gender: ♂
Member of: Lilin

Outcasts
Outer Circle of Enforcers I
Outer Circle of Enforcers II

Member(s): Vanisher

Outlaw

Inez Temple
Gender: ♀
Individual of: Mutants

Main
Domino Annual 1
Domino TPB (II) 2

Features
Deadpool Corps: Rank and Foul 1.FT

Outlaw Kid
Outlaws
Overdrive
Overlord
Overmind
Overrider

Richard Rennselear
Gender: ♂

Features
Wolverine Encyclopedia 2.FT

Oversword
Ovoids
Owl
Owl Gang

Member(s): Owl

Ox I
Ox II
Oya

Idie Okonkwo
Gender: ♀
Alias of: Idie Okonkwo
Member of: Generation Hope

Oyakata
Ozymandias