MAME 2015 (Page 208)
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Off the Wall 2-player cocktail
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Ougon no Shiro Japan
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Oh! Bakyuuun Japan OB1/VER.A
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Oh My God! Japan
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Oh! Paipee Japan 890227
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Oigas bootleg
Oishii Puzzle Ha Irimasenka
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Ojanko Yakata 2bankan Japan
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Ojanko Club Japan
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Ojanko High School Japan
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Ojanko Yakata Japan
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Ojousan Japan 871204
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Ojousan [BET] Japan 870108
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Oriental Legend Special / Xi You Shi E Zhuan Super ver. 103 China Tencent unprotected
Omega
Omega Fighter
Omega Fighter Special
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Omega Race set 1
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Omega Race set 2
Omni
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Omotesandou Japan 890215
One Shot One Kill
One + Two
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