Oka Hachirou is an almost legendarily skilled Gantzer, a veteran of a very large number of games, he was said to have gained a hundred points at least seven times. Oka is a brilliant tactician and hand-to-hand fighter, using all of his equipment to his advantage. He uses his advanced suit's abilities to stay invisible and hidden while his team kills the small aliens and he focuses on the stronger ones (though this isn't necissarily true for every single mission he has been on).
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with Reika
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http://homepage1.nifty.com/musuke/ko...kou_gantz.html