Update 2.0:

Intralism - fast and hard arcade. Listen to music and match notes. Master all levels or create your own and challenge friends with online multiplayer. But remember: wrong button - failed try.
The main focus of development was on the level editor and multiplayer. Players are able to easily add their favorite music into the game and play it with friends.

Features:

[ Challenging Gameplay ]
For competitive players only. In the Intralism you need all of your reaction and an ear for music

[ Custom Levels ]
Subscribe and rate an interesting levels in Steam Workshop created by other players and become #1 in the online leaderboards

[ Levels Editor ]
Have an interesting idea for level? Create your own with editor and play it in multiplayer with friends via Steam Workshop

[ Multiplayer Up To 16 Players ]
Challenge your friends' skills in the online battle

[ In-game Items ]
Customize game with rare items or sell them on Steam Market

[ Achievements ]
Hidden and multiplayer achievements don't let you get bored. Try to master this game!

[ Online Leaderboards ]
Track your progress with leaderboards

[ Steam Trading Cards And Emoticons ]