The rebels have captured several star-cruisers and are about to launch a major offensive against the Empire, but operating these formidable ships requires a lot of energy and the Resistance lacks the necessary power sources.

Several pilots have been commissioned by the Resistance to enter the Imperial bases and retrieve the "Klystron pods", an essential power source for the star-cruisers.

[1][2][3] The gameplay of Zarathrusta is similar to that in the original game Thrust, where the player controls a small spaceship that is constantly subject to gravity and the craft's inertia.

The player has to rotate the spaceship, fire its weapons and thrust its engines to carefully navigate the planet's cavernous landscapes, retrieve the Klystron pod and escape to the orbiting mothership.

[1][6] The player can use the tractor beam to grab the Klystron pods, but also to absorb energy from alien inhabitants and fuel tanks which are scattered around each planet.

[4] During the course of the game, players will encounter three different types of Klystron pods (Standard, Hydrogen and Basket), all found atop a tall plinth somewhere on the surface of the planet.

In the December 1990 issue of The One, Hewson Consultants, Zarathrusta's publisher, stated that the pair were inspired by Jeremy Smith's 1986 video game Thrust.

[7] Robaye was a big fan of the Commodore 64 game and wanted to create a 16-bit version of it, with more levels, enhanced graphics and improved features.

Robaye was very enthusiastic about the project and spent his nights after coming home from high school creating the game's graphics.

He compared the game to Thrust noting that "there has been a lot of work done on producing some nice colorful graphics and effects, but the same feel has been retained".

On top of the enhanced presentation, "the extra enemies and weapons add a nice new twist", making it "a more involving blast".

[2] Steve White of Amiga Action said that "Zarathrusta will bring tears to the eyes of seasoned gamers as they remember the good old days long ago, when they stayed up all night playing Thrust.

Editor Tom Malcolm felt that the presentation was "top-notch", praising the game's sound effects and graphics, especially the backgrounds which "are animated and have that beautifully drawn, hard-edged European look".