Well I don't think Mat's egos are really agreed upon like antisepticeye and darkiplier are seeing as not many of the GTLive fandom really play around with the egos (unfortunately). Madpat is like the most known, antimatter could be the same or a completely different depending on the person's interpretation, and taptam had been referenced by mat and Steph on the streams when they were playing around with the names of a dark side of Mat.
I am intrigued by this. Perhaps this blog should bring TapTam to life?
OMG I JUST REALIZED TAPTAM IS MATPAT BACKWARDS *proceeds to throw my phone out the bus*