Great game! Only thing that could be improved is the rating system; when an opponent leaves the game, your rating should still increase. It is unfair that just before you win a battle, the opponent leaves, and your rating does not increase.
A definition on what each stat (Skill, Power, Agility, Mentality) does, and how they affect a player's performance in game would be nice. I mean we can make assumptions for most... but mentality?
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It should increase. You may just be fighting someone lower ranked than you (which wouldn't increase your rating)