The Worst Knex Mod Ever. By tinyhooman in LivingLEGO & K'NEX387Save PDFFavoriteIntroduction: The Worst Knex Mod Ever.By tinyhoomanFollow More by the author: About: I’ll be back making instructables soon, took a long break from doing these More About tinyhooman » Because I'm stupid, I modded a good slingshot pistol into a crappy hammer action that shoots black y clips like 2 ft