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- Ocean Ranger (1988) C64, DOS
- Oink! (1983) ATR26
- On-Court Tennis (1984) C64
- Orphen: Scion of Sorcery (2000) PS2
- Over the Hedge (2006) GCN, PS2, Win, Xbox
- Over the Hedge: Hammy Goes Nuts! (2006) NDS
Read more about this topic: List Of Activision Games