Falci: The first Guilty Gear came out in 1998.
Today, after almost 20 freakin' years, I finally understood that Zato-1 is a reference to Zatoichi.
*facepalm*
But I'm happy, nevertheless, for understanding why the character has such a weird name.
Is the Zatoichi Bo (not Bow; you don't shoot arrows with it) found in some Wizardry games (including Wizardry 8), by any chance, a reference to Zatoichi? (If it helps, in Wizardry 8 this weapon is classified as a quarterstaff, is only usable by Samurai and Monks, and can be used to cast Blinding Flash.)
(I have actually never heard of Zatoichi, to be honest.)