Your first mission out of Space College could hardly be tougher - penetrate the SS Future spaceship, and activate its self-destruct function, to prevent it crashing into earth. This means walking through 256 screens of minions, and getting each part of the protection code.
The droids emerge from particular points of the level, and constantly regenerate, so your path must be precisely navigated. You can collect a suit of armour for protection, improved weaponry (the initial unit only fires horizontally), and a high-speed scooter - each of which last for the next 3 screens. Extra lives can be collected en route.