Xexex is pronounced "Zek-seks". This name comes from the 1991 Konami arcade game, Xexex from which "Flint Lock," "Flint," and "Flint Missile" are also taken. The card may also be named after the Persian king Xerxes.
The armour seems to resemble Kaioh's armour. Kaioh is the final antagonist of the Hokuto no Ken series and is also sometimes referred to as Emperor of Destruction.