The Hosts are the top layer of this. They're the farthest in the turns, originating in the supposed 13th turn. The 13th is the last of this specific order of events (that eventually lead to self-destruction).
But there's also the second layer of this metaphorical onion of timelines.
The
Overseers are the leaders of the 12th turn and partially the reason of all of this bulls***.
The Operator: A being of unknown origin. He has many supposed cousins in appearance, such as the Slenders. He has also been compared to a more humanoid version of a windigo. He has been perceived as a being of higher intelligence and awareness. He seems to focus a lot on balance. He collects proxies to do his dirty work for him, favoring misshapen dirtied souls for such tasks. He is the closest equivalent to a "good" force in this.
The Demon: Also known as Zalgo and other names. Seems to be a knock off Satan (to put it lightly). His appearance varies with the names but he seems to have the basic template, as the name suggests, of a demon. Instead of proxies, he has servants. He also tends to favor the dark and twisted. He is the equivalent of a lesser "evil" force.
TOBI: With an unknown appearance, true name, motive, or even an inkling upon his origin, TOBI is the true malevolent force. He has been linked to causing the end of the last eleven turns. He is known as "John" by his mandatory host, Andrew. As far as we know, he has masked his true motives in world domination based upon clean cut cliche good vs evil tactics. Thought a first to be a third party who lacked relations with either The Operator or The Demon, TOBI is best described as a "Neutral" force.