Ugh...I have more than one...
-Osu!
*A game in which you have to hit boxes on a certain rhytm, fun and challenging
-Touhou
*A must play for Danmaku lovers. Danmake being a curtain shooter also known as a shump (Shoot 'em up). Simply said, a hard game with tons of bullets and sometimes a patterns sometimes random bullets. Extremely challenging (Be asian or play on easy / normal).
-Grand Chase
*Not really my favourite but fun to chat in and waste time...
