|Episode:||The great escape with wounds all over|
|Season:||Uchuu Keiji Shaider|
|Voice Actor:||Eiji Maruyama|
Gasgas (ガスガス Garugasu?): A spiked Fushigi Beast with nunchaku and able to spew gas, created as part of a Fuuma scheme to use the anti-Vavilos device they are developing to negate Shaider's remote transformation. When Dai falls for the trap, he is unable to become Shaider as he forced to run for his life while subjected to the poison gas. However, Annie actives the Shokatsu System manually to save Shaider as he proceeds to destroy the machine. Chasing Gasgas into the Fushigi Dimension, Shaider fights through the monster's red-helmeted, commando-garbed grunts before knocking the monster's broadsword away to destroy it with Shaider Blue Flash. Its powers include invisibility, a chained mace and kanabo that can emit electric shocks, high jumping, choking mouth gas, telekinesis, teleportation, size changing, eye bombs, dividing into three swordsmen with choking gas and laser guns and a sword that emits sparks.