Callahan has decided to step out of the sidelines and play with the Dream Team.
Callahan is not like everyone else on the Dream Team. He is not searching for the spotlight. He has been known as a selective mute, which means he chooses not to talk and just uses game chat every once in a while.
Those in the know have said that Callahan has been on the Dream Team since it started. There are even instances where he has been mentioned.
It is Callahan's mysterious nature that has brought him so much attention since he started being open to playing on streams. Even some of his own teammates have forgotten what his voice sounds like.
Here is a clip of Quackity pretending to sound like Callahan and doing a good job of fooling a Dream Team member.
Related: Sapnap reportedly drove to Dream's house for a meetup, and the internet can't get enough of it
Callahan will most likely not be moving the Dream SMP narrative or story anywhere and will only be playing alongside the others. This technically makes Callahan more of an NPC than an active participant, but he likes to play his way and no one can fault him for that.
Related: Addison Rae could join the Dream SMP next after a recent Twitter exchange with Karl Jacobs
Callahan has a mighty Twitter following, but most of his tweets seem to not really relate to anything
When his tweets do seem sensible, they're at the tail end of conversations or pranks. It is almost as if he chooses not to participate in any of the shenanigans. This sounds a lot like him because he has only recently chosen to participate in a server he helped build.
Whether he will decide to be a more active participant in the Dream Team or the Dream SMP storyline remains to be seen.
Related: A full exploration of the Dream SMP Minecraft seed