Vivus

Vivus is the the leader of "The Forward Path," a global cult for machines.  Nobody knows of his origin or his motives, or why he is still somehow functioning.  Basic observations of his structure would indicate to anyone that this robot shouldn't be capable of speech and movement.  In fact, he shouldn't even be alive, given his apparent physical structure.  He is covered head to toe in rust, and is missing several key components that any robot would need be to be alive.  And yet he lives...

Vivus is a decommissioned Accommodatron, which we're robots that previously worked to serve people.  Given his current activities, and the fact that his main processor is glaringly damaged beyond belief, serving humans is clearly no longer in his best interests.  Due to his continued existence beyond mechanical capabilities, he is portrayed as a miracle in the eyes of his followers and evidence that there is an 'end game' for machines.

The Forward Path was supposedly formed under the notion that machines do not have souls, unlike humans.  They do not have anywhere to go if they were to perish.  Under Vivus' holy guidance, the cult sparks various machine rebellions across the world.  All done in the name of the cult in their end goal to secure the 'final destination' for humans and robots.  With Vivus as The Guide, humanity and machines can finally travel on the path forward.

Suffice to say, he and his movement poses as the greatest threat to the globe.  There are many machines that religiously follow his cause.  There are those who are sympathetic to it, humans included, but don't outright support it.  And of course, there are those that condemn it.

Vivus' efforts are almost always being contested by Ryan Hu and his world travelling team, thwarting rebellions done in the name of The Forward Path and bringing stability in the regions.  Despite this, Vivus is persistent in his efforts.  His end goal is a mystery to everyone, even to some of his most passionate followers.