splinter's sons, along with their new friend april o'neil, soon become involved in the conflict with both of splinter's old enemies, the shredder and the kraang. reluctantly allowing the group to get involved, splinter appoints leonardo as their leader and continues to offer counsel and lessons as they engage various foes. recognizing great sensitivity in april, he begins training her as a kunoichi and comes to regard her with a fatherly fondness. splinter ventures from his lair on only two occasions. the first is when he falls under the control of the rat king, who attempts to persuade him to forsake his humanity and embrace the life of a rat. splinter eventually breaks free with the turtles' help and defeats the rat king. the second is when shredder kidnaps april and lures splinter to his stronghold for a final confrontation. splinter overpowers shredder's men and engages his old foe. shredder reveals that splinter's daughter, miwa, had not died and that shredder had taken her and raised her as his own. splinter nearly defeats shredder, only to be attacked by miwa; miwa, whose name is now karai, has been taught, by shredder, that splinter is responsible for her mother's death.