INSTRUCTORS
Our team brings unmatched experience to the mats. As the only gym in Tarrant County with multiple black belts in both Brazilian Jiu Jitsu & Judo, we're proud to offer a training environment where students of all ages can sharpen their skills, build confidence, and learn from the very best. Open in Keller, TX, since 2007, we have a massive student base from white to black belts to help you on your journey!
ROBERTO KAELIN
BJJ & Judo Black Belt
Roberto is the Owner & Head Professor of Viper BJJ. He moved to the US at the age 18 from Peru to train under world-famous BJJ instructor, Carlos Machado. Roberto earned his Black Belt in 2005 and then opened Keller's first Brazilian Jiu Jitsu academy in 2007. He has trained hundreds of students who have improved their lives, earned black belts, opened their own academies, and become IBJJF & tournament champions!
BJJ Black Belt | 4th Degree | Under Carlos Machado
Judo Black Belt | 1st Degree | Under Vince Tamura
Karate Black Belt | 1st degree | Under Wayo Salas
TRACY D'ARCY
BJJ Black Belt | Judo Brown Belt
Tracy has been the office manager, kids class instructor, and women's only program instructor at the academy since its inception in 2007. Her philosophy has always been to run the school with honesty, integrity, and hard work. Tracy's passion is teaching BJJ and making the art easy for everyone to learn!
BJJ Black Belt | 3rd Degree | Under Roberto Kaelin
Judo Brown Belt | Under Dwan Stregles
TREY PEERY
BJJ Black Belt
Trey Peery is a BJJ Black Belt under Roberto Kaelin. Since 2020, Trey has led our morning classes, growing attendance from a single student to a strong, dedicated core through a focus on fundamentals and personal attention. His teaching style emphasizes technical basics & adapts to the needs of each student, fostering skill development in a supportive environment. Trey is passionate about helping others progress and tailoring training so every practitioner finds their path in jiu jitsu.
DWAN STREGLES
Judo Black Belt | BJJ Black belt
Dwan is a 6th Degree Black Belt (Red & White Rank) in Judo & leads our Adult Judo program. He is a multiple-time Texas State Judo Champion, 2x National Judo Champion, and also holds a Black Belt in BJJ.
WESLEE PARKER
BJJ Purple Belt
Weslee is an active competitor with a passion for learning. He leads our kids competition team classes & is a great example for our champion kids team. At Blue Belt, he won gold at every local tournament, plus silver at IBJJF Pans & Master Worlds in 2025. He was promoted to Purple Belt in September 2025 & won the AGF Purple Belt Master division that same month!
DARION JACKSON
BJJ Brown Belt
Darion is our Kids & Teens MMA instructor. He is an active competitor in several martial arts including Brazilian Jiu-Jitsu, MMA, and Muay Thai Kickboxing.