Extract it to your RetroArch save directory. It should work with PCSX-ReARMed and the beetle core. I can't say if it'll work with DuckStation as I haven't personally given it a shot yet.
Anyways, Tekken 3, one of the best fighters on the PS1, and easily the best out of the Tekken games on the system. It's actually pretty easy to unlock mostly everyone yourself (Dr. Bosconovitch requires you to defeat the Tekken Force of the Mishima Zaibatsu itself, and Gon requires you to knock a ball into the little guy), but this cuts out on all of the grinding!
Anyways, Tekken 3, one of the best fighters on the PS1, and easily the best out of the Tekken games on the system. It's actually pretty easy to unlock mostly everyone yourself (Dr. Bosconovitch requires you to defeat the Tekken Force of the Mishima Zaibatsu itself, and Gon requires you to knock a ball into the little guy), but this cuts out on all of the grinding!
