ASWD or arrow keys to move. spacebar to attack. if after buying dark siren head or crystal demon siren head you spawn in as wood siren head, just press spacebar and you should turn into the siren head you bought. if you buy both siren heads it basically breaks the game so just press the green flag to reset it and just use the global siren echoes to buy the one you want.
the purpose of global siren echoes is to make it so other people who might not have enough time to play and unlock them can get them right from the start, and other people might need more siren echoes, so they use the global ones instead. it basically forces you to be nice. if you have any suggestions please comment them so i can modify it to everyone's liking. e.g. new siren heads to add in the store, game mode ideas (if I can code them) etc.