Jokerkind is a form of Strife Specibus employed by Gamzee Makara. The jokerkind strife deck to allow the user to employ certain weapons with proficiency, and although the criteria are unknown, it's speculated that any weapon can be equipped as long as it looks funny. There seem to be 20 cards in the deck. Some have yet to be seen. Likely meant to be used in a similar manner to the Joker in a deck of cards, which can basically be any card that the user wants it to be. How Gamzee acquired all the weapons is unknown, though they were likely obtained through a combination of alchemy and pilfering from various chests. This specibus may also be a reference to the Insane Clown Posse, as all of their album covers are joker cards.
Some theorize, though guardians originally needed no strife decks, that this specibus is the one used by John's Dad, as he wields a number of different weapons such as a cake, a can of shaving cream, his own fists, and a safe at various times during the comic.