 He was temporarily de-aged during the Incursion between Earth-616 and Earth-1610.In Marvel Comics #1000, it was reveal that Jerry was a subject in a side project of Project Rebirth, the government project that create Captain America, called Project Thunderer.Thunderer's mask is a magical item called the Eternity Mask, which was created by a group of renegade occultist from Eternity's own substance in the days of King Arthur.