Justice League Quarterly #3

Synopsis

Following a meeting between the American and European teams, Mitch Wacky and Kilowog use a dimensional time transporter in an attempt to save Mitch's world from nuclear devastation. A team of Captain Atom, Fire, Blue Beetle, Guy Gardner, Ice, Power Girl, Flash, and Silver Sorceress follows them to either save them or stop them. Part of the transporter technology is Imskian-based, causing anyone who uses it to shrink. Both teams discover that the past can't be changed and while returning to their own time, the group accidentally gets shunted to the original JLA's time before making it home.