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One Piece chapter 1109
(tcb.abhayaby.com)
Wow, the summoning of 4 other elder stars using the same summoning circle that Saturn used was crazy. And the Gorosei can use telepathy somehow, how did the communicate without den den snails from Meri-Jose to egghead?
Also it seems like one of the Gorosei needs to physically travel close to a location to summon the others.
Maybe the 5 Gorosei combined will manage to interrupt the broadcasting of Vegapunk, once he gets to the most interesting point of his message to the world -- that would be typical Oda fashion.