Teenage Mutant Ninja Turtles Adventures 1989 #12 Direct ed. - back issue - $4.00
Krang chases Cherubae and the Turtles into Dimension X in pursuit of the Turnstone. He is able to force Cherubae to drop the artifact but it lands on the planet below. He sends Shredder out to get it but also asks for Maligna's help in recovering the stone. Meanwhile, the Turtles resolve to find the Turnstone first and Cudley shows up with reinforcements to help them look.
Comic has at least 2 printings.
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