Founding members of these eight superhero teams in question

The eight being the Teen Titans and the X-Men as well as their first three spinoff teams that had their own comic book series.

Teen Titans

• Richard "Dick" Grayson / Robin
• Wallace "Wally" West / Kid Flash
• Garth / Aqualad
• Donna Troy / Wonder Girl
• Roy Harper / Speedy
• Lilith Clay / Lilith
• Raven (NTT incarnation)
• Garfield "Gar" Logan / Changeling (NTT incarnation)
• Victor "Vic" Stone / Cyborg (NTT incarnation)
• Koriand'r / Starfire (NTT incarnation)

X-Men

• Charles Xavier / Professor X
• Scott Summers / Cyclops
• Robert "Bobby" Drake / Iceman
• Henry "Hank" McCoy / Beast
• Warren Worthington III / Angel
• Jean Grey / Marvel Girl
• Lorna Dane / Polaris (ANAD incarnation)
• Alexander "Alex" Summers / Havok (ANAD incarnation)
• Kurt Wagner / Nightcrawler (ANAD incarnation)
• James "Logan" Howlett / Wolverine (ANAD incarnation)
• Sean Cassidy / Banshee (ANAD incarnation)
• Ororo Munroe / Storm (ANAD incarnation)
• Shiro Yoshida / Sunfire (ANAD incarnation)
• Piotr "Peter" Rasputin / Colossus (ANAD incarnation)
• John Proudstar / Thunderbird (ANAD incarnation)
• Moira MacTaggert (ANAD incarnation)

Team Titans

• Miriam Delgado / Mirage
• Tara Markov (Stratan doppelganger) / Terra
• Carrie Levine / Redwing
• Dagon / Nightrider
• Charlie Watkins / Killowat
• Jonathan Levine / Prestor Jon

New Mutants

• Charles Xavier / Professor X
• Samuel "Sam" Guthrie / Cannonball
• Xuan Cao Manh / Karma
• Danielle "Dani" Moonstar / Psyche
• Roberto "Bobby" da Costa / Sunspot
• Rahne Sinclair / Wolfsbane
• Douglas Ramsey / Cypher
• Illyana Rasputina / Magik
• Amara Aquilla / Magma
• Warlock

Young Justice

• Timothy "Tim" Drake / Robin
• Kon-El / Conner Kent / Superoby
• Bartholomew "Bart" Allen / Impulse
• Greta Hayes / Secret
• Cassandra "Cassie" Sandsmark / Wonder Girl
• Suzanne "Cissie" King-Jones / Arrowette

X-Factor

• Scott Summers / Cyclops
• Bobby Drake / Iceman
• Hank McCoy / Beast
• Warren Worthington III / Angel
• Jean Grey / Marvel Girl
• Cameron Hodge
• Arthur "Artie" Maddicks
• Tabitha Smith / Boom-Boom
• Russell "Rusty" Collins / Firefist
• Leech
• Julio Richter / Rictor
• Sally Blevins / Skids

Titans

• Dick Grayson / Nightwing
• Wally West / Flash
• Garth / Tempest
• Donna Troy / Troia
• Roy Harper / Arsenal
• Victor Stone / Cyborg
• Koriand'r / Starfire
• Grant Emerson / Damage
• Antonia "Toni" Monetti / Argent
• Jesse Chambers / Jesse Quick

Excalibur

• Kurt Wagner / Nightcrawler
• Katherine "Kitty" Pryde / Shadowcat
• Lockheed
• Rachel Summers / Phoenix
• Brian Braddock / Captain Britain
• Meggan Puceanu