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Exol is a Cipher grunt. He has a higher rank than a regular Cipher Peon, but a lower rank than a Cipher Admin. He is much more muscular than a typical Cipher Peon is.
He and a team of Cipher Peons under his command invaded the ONBS headquarters to recover a Data Rom that was stolen from the Shadow PKMN Lab by Michael. He held Nett's sister, Megg, ransom for the Data Rom. Nett was forced to return the Data Rom. After releasing Megg, Exol revealed that he had had his Cipher Peons delete all the data recovered from the Rom by Nett from ONBS's database. He is the only character in the games to have the Trainer class Cipher Cmdr, an abbreviation for Cipher Commander.
When he tried to leave, Michael confronted him. Michael beat Exol, snagging his shadow Mawile in the process. Exol and his Peons fled, and were never seen again.