Colony 7

Colony 7 is a single screen arcade shooter where you, the player is in charge of defence of the colony. There is a shield that protects the settlement’s power generators that is under constant attack from ‘Jarvian’ alien invaders. There are two pulse cannons that can be used to shoot down the Jarvians, but an innovation of the time is that you can buy additional weapons for extra credits. The player has at his disposal a range of more powerful weapons that can be set off for a limited amount of times per game. A Mega-Blaster can be set off that destroys everything within its radius using up fuel reserves on the ground and a once per game ‘Eradicator’ that destroys every alien on screen.
The game mixes the play style of a conventional fixed screen shooter with that of Missile Command since your pulse cannons can be taken out, rendering you defenceless.