Gekko is the youngest member of the team but he's a strong and sticky master of camouflage! He's ready to rush into danger and save the day with his super Gekko muscles. Always ready for action, Gekko can scale walls and with his Gekko-mobile so can all the PJ Masks! It can even travel underwater... Watch out baddies, here comes the mighty Gekko! In Season 2, it is revealed that Armadillain is his former friend along with Catboy and Owlette. At first, Armadillain likes him because he is also strong. But later, Armadillain doesn't like him anymore as he swore revenge on him and his two teammates because he, Catboy and Owlette kicked him off their team for being too reckless.
As Greg, he can sometimes be competitive when it comes to playing games, but he isn't very good at rhyming (as evidenced in "Speak UP, Gekko!"). When he isn't Gekko, he isn't as strong and that sometimes causes him to doubt himself. This is usually remedied by Connor and Amaya's encouragement. He's also nice, friendly, helpful, somewhat shy, fun, playful, and funny.
As Gekko, he pretends to be Kick McGee along with Catboy playing as Master Fang during missions. He sometimes displays insecurity, such as in Gekko's Super Gekko Sense when he made up a new power due to thinking that the powers he actually had would now help win the game. He can be easily distracted (which was emphasized in "Slowpoke Gekko"). Like his fellow teammates, childlike immaturity tends to overtake his mindset on the mission leading to issues (such as rejecting Owlette's desire to play along as Flossy Flash with them in "Catboy and Gekko's Robot Rampage"), but this is always realized and corrected leading to the mission being done properly, and the villain's plans foiled.
Greg has fair skin, blond hair, and green eyes. His daytime outfit consists of a light green sweatshirt with a lizard image at the center and a pair of tan pants. The outfit of Greg's nighttime hero, Gekko, consists of a green lizard jumper and mask.
- Greg is friends with Connor, Amaya, and Cameron, and considers them best friends.
- Greg is the youngest of the group.
- He has a love for reptilians, especially lizards.