There are two factions in Slender.Io 2D shooting game. Your mission will depend on the role that you are given. So, it is feasible to play as a man or a scary monster which is known as Slenderman. If you are chosen to start off with a member of the human party, you need to collect all of the missing notes in Slender.Io online as fast as possible and use them to buy stuff in the shop. In case you join the adventure unblocked as a mutant, you must catch people or block them from gathering pages. Have fun!