#6 Batman: The Brave and the Bold: The Eyes of Despero!
This wasn't Guy Gardner's first appearance on screen or even on The Brave and the Bold, but it was the first time he got to be a hero. The episode also teased the evil Sinestro, who in this episode was still a Corps member.
Also, we got Mogo, G'nort, Despero, the Oath, and Bat-Lantern all adding to one of the greatest Green Lantern adventures ever committed to film.
#25 - Justice League Unlimited: Initiation - John Stewart's new look
#24 - Batman: The Brave and the Bold: Death Race to Oblivion! - Guy Gardner's Lanternmobile
#23 - Justice League of America: Pilot - Doesn't air
#22 - Justice League Unlimited: The Once and Future Thing: Time Warped - Hal Jordan joins the league
#21 - Legends of the Superheroes - Lantern goes live-action
#20 - Justice League: Crisis on Two Earths - Darker shade of green
#19 - Batman Beyond: The Call - Lantern of the future
#18 - Static Shock: Fallen Hero - Hero worshiped
#17 - Batman: The Brave and the Bold: The Revenge of the Reach! - Loads of Lanterns
#16 - The Batman: Ring Toss - Gotham by greenlight
#15 - Justice League: Hearts and Minds - More to the Corps
#14 - Justice League Unlimited: The Return - The Corps is greener yet
#13 - Justice League: The Savage Time - Ringless
#12 - Batman: The Brave and the Bold: Day of the Dark Knight - Guy is the man
#11 - Justice League: Legends - The Green Guardsman
#10 - DC Heroes: Justice League of America: Between Two Armies - Joining the League
#9 - Challenge of the Superfriends: Secret Origins of the Superfriends - Secret origin of Hal Jordan
#8 - Duck Dodgers: The Green Loontern - Looney Lanterns
#7 - Justice League: Secret Origins - John gets the limelight
#6 - Batman: The Brave and the Bold: The Eyes of Despero! - Guy the hero