Trion Juggs was the one who punched through dimensions
Trion, possessed Juggy, and unleashed the full power of the aspect of Cytorrak, and Juggy grew thousands of feet, could destroy realities (as that's what the evil wanted him to do), and his punches were so powerful and forceful that they tore through the very fabric of reality. Imagine a being so strong that it could crush something into a black hole, Juggy became stronger than that, more powerful than that. He eventually overcame the tremendous psionic entity possessing him, and he went back to normal size as he was in control again. Since then he seems less powerful than his post XMU 11 self, and is now just 2x as powerful as his pre-XMU 11 self, as evidenced in his recent Thor appearence during the 8th day.
8th Day happened before the Trion incident. The Trion were 3 beings. Their enemy is what possessed Juggernaut, NOT the Trion. It mentions that it could be Cyttorak possessing Juggernaut, but it also hints to a different force possessing him. When Juggernaut grabbed the fake gem he was possessed by it's creator. It didn't say if it was Cyttorak that created it or not.
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