The Flash #102

The Plot: "Running Away"

Mongul, the alien tyrant and destroyer of Coast City, has arrived in Keystone City on a mission to recover a spacecraft buried deep beneath the city.

• The Ultimate Matchup: This issue is famous for showing just how powerful Wally has become. Mongul is a "Superman-level" threat, but Wally uses his new ability to steal kinetic energy to slow the titan down, effectively turning Mongul into a living statue.
• The "Engine City" Connection: The story ties back to the Death and Return of Superman lore, as Mongul searches for remnants of his previous Earth invasion.
• Wally’s Confidence: After the self-doubt of the "Terminal Velocity" arc, this issue showcases a Wally West who is finally comfortable in his own skin—and his own speed. He isn't just a sidekick anymore; he's a heavy hitter.