Mission #18: Fear No Evil
It's time to take on Prometheus. If you've sustained any damage from the previous missions and are missing weapons, you might want to restart at Mission #16: A Spear in the Dark if you've saved the game from there, because you're going to need everything - Prometheus is very tough.

	It's that bad boy Prometheus himself.

One strategy on Prometheus is that you don't actually have to duke it out point-blank with him. You can actually sit atop the valley rim and draw him out with fire. You can't climb the valley wall, so you can pound Prometheus from long range (with little fear of missile attack - Prometheus doesn't have any) with missiles of your own. That assumes that you're overloaded with missiles.

Another way is to duke it out with him, which is dangerous - if he hits you twice with a full broadside, you can forget about finishing the mission, if you haven't already been blown up. You must be very accurate - take out a few of his weapons if you have the accuracy. Try to stay behind him at all times where he can't get at you, but he's faster and quicker than he looks. It will take a lot of fire to take down Prometheus because he also has regenerative armor and shields. Taking out a leg is always a feasible move, but be prepared to try for a long, long time.

Good luck!