You can quickly and easily log in with any existing account you have. After authentication, we will ask for your email and a screen name. Once logged in you can still set up a local password and/or link your other accounts in the account management. The nice thing about linking all accounts is that you don't have to worry about logging in with the "wrong" one and accidentally creating multiple accounts. If you play Holodance and/or Beat the Rhythm on Steam, logging in via Steam is the quickest way to access your gameplay data from here.