2) The Hand
The Kingpin deals with several criminals and organizations in his efforts to “save” Hell’s Kitchen: The Russians, Madame Gao, and a Japanese businessman named Mr. Nobu, who’s later revealed to be a badass red-suited ninja, which is an obvious nod to The Hand.
The Hand is an ancient cult of evil, mystical ninjas involved in organized crime and assassination plots. Their biggest enemy is The Chaste, a band of warriors who were once in the Hand but left because they didn’t agree with the cult’s more sinister activities. The Chaste is led by Stick, which explains why he reappeared in Hell’s Kitchen seeking Matt’s aid in stopping some “weapon” that Nobu’s shipping in called Black Sky.
With Stick and Stone hoping to bring Matt into the Chaste, and the Hand slowly finding their way into Hell’s Kitchen (they own a bunch of property now, thanks to Fisk), it’s only a matter of time before Daredevil turns into an all-out ninja extravaganza.