Announced during Evo 2014, the KI tournament originally only allowed players who have been consistently playing in events like Evo 2015, Kombo Klash competitions hosted by Ultra Arcade, and other major events.
According to the official website, registration is open to the public so feel free to register online and receive your badge for the tournament. Over 300 people have already registered. Tournament rules and regulations are all on the website, as well as point distributions and format.
PAX South will be in San Antonio, Texas this year from January 29-31. You can register on their website, here. Tickets cost $35 per day and the three day passes are all sold out so you will want to hurry if you want to go. The website also comes with hotel information, a printable copy of the schedule, and more.
Xbox Live Gold Members can play Killer Instinct Season 1 Ultra Addition for free this entire month of January. Season 3 will be available this March for Xbox One and PC.