Oya and Fuji would also increase the numbers in Lethal Weapon by recruiting Mr. Pogo, The Gladiator, and Horace Boulder.

In August 1995, during a round-robin tournament for the vacant FMW Brass Knuckles Heavyweight Championship, Oya fought Hayabusa to an epic 30-minute time-limit draw.

In September 1996, Lethal Weapon disbanded and Oya joined Funk Masters of Wrestling, where he formed a trio with The Headhunters and won the FMW World Street Fight 6-Man Tag Team Championship.

After the Funk Masters disbanded, Oya decided to turn face for the first time in his career and join forces with Hayabusa.

Up until the demise of FMW in February 2002, he fought alongside Hayabusa in his wars against Mr. Gannosuke and Kodo Fuyuki.

During his stint in WMF, he developed a Puerto Rican assassin gimmick named HISAKATSU.