Super Scribblenauts was published in Japan by Konami (which also handled the original Scribblenauts). That explains why Solid Snake, in this image tweeted by Metal Gear creator Hideo Kojima, shows up in the game. Snake’s got company, too.
The Vic Viper fighter from Gradius also can be created. Manaka from LovePlus can be summoned to give Maxwell some company.