Lifeogen is a substance used by Shredder in the Teenage Mutant Hero Turtles Adventures comic The Un-Nice Ice-Cream Scheme!.
When free ice cream cones given out around the city begin coming to life, and even the Turtles are attacked by an Ice Cream Creature in their own lair, the green team heads out to investigate. They pick April O'Neil up in the Turtle Van and go to the Creamy Cones factory. Though Uncle Creamy denies anything untoward is happening there, he slips a key into April's hand before going back inside the building. The key opens a back door and the Turtles and April enter. They reach the mixing room and from a hiding place, spot Shredder threatening Uncle Creamy by reminding him that Bebop and Rocksteady are holding Uncle Creamy's granddaughter. Shredder proceeds to add a substance called "Lifeogen" to the ice cream vat and explains that this will cause the ice cream to come alive as soon as someone licks it. The Un-Nice Ice-Cream Scheme!