WorldKiller (SPI) Review & How to Play

About WorldKiller: The Game of Planetary Assault, from BoardGameGeek:

WorldKiller: The Game of Planetary Assault, is a Tactical level simulation of the classic Science-Fiction theme of planetary assault. In the standard scenario, one player commands the ships and orbital fortresses of the defending Human forces; and the other player commands the ships of the attacking Alien forces. Beyond the standard scenario there are provided additional rules and types of ships for players to devise their own scenarios. A small wargame with 4 pages of rules, a 11"x 16" fold-out map sheet and 100 die-cut counters. Originally published in Ares magazine Nr.1 (March 1980)