Grendizer, the UFO robot, travels in his Spazer saucer.  In air battles, Grendizer is connected inside Spazer.  As a unit, this machine is an excellent fighter in the air.  Duke Freed will brilliantly out-maneuver the enemies in many battles.  Many times in air battles, Grendizer will take down the enemy before shooting out of Spazer for the battle on the ground.

Spazer as a stand-alone unit is also a great helper when Grendizer gets into trouble.  I feel that it should have been used more often.  For example, in the battle with the Vegan bodyguard Captain Gorman, Duke Freed was nearly defeated.  If Duke Freed wasn't trapped in his fears then he could've used Spazer to come from behind and nail the Vegan bodyguard's mecha "Gin Gin".

Other times Grendizer will actually stand on Spazer and use it to jump off of when fighting an enemy in the air.