Protectors (not to be confused with Protectors II), is a loosely based on the arcade smash Defender. While it has no humans to rescue, it does have a wider variety of enemies than the arcade original; it also has several enemies that are ground based as opposed to flying. A side note: SYNAPSE SOFTWARE had a game called Protectors for other platforms; when it was ported to the Coco, it was changed to Protectors II, to avoid a name conflict with the already existing Tom Mix game. Protectors was a little unique (and a little awkward to use) because it required 2 joysticks to play.
Title: Protectors
Author: Ron Beatty
Publisher: Tom Mix Software
Released: October 1982
Requires: Color Computer 1,2 or 3, 32K RAM, cassette or disk, 2 joysticks.