Shadow Complex

You will receive this achievement at the end of the final cutscene, upon defeating the final boss.

*tips for boss at bottom*

//NOTE//
If you have initiated the cutscene that allows you to fight the final boss at the lake, bear in mind it becomes impossible for you to collect the three items in the elevator to the furthest right of the map, aswell as the 'Walkin' on Water' achievement. It would usually require you to go down the elevator, go all the way around the map then come from above, as far as I know. If you activated the scene, the final boss will interrupt you as you're going around, thus becoming unable to get those items. I learned this the hard way, missing those three items and thus the final helmet, ending on 96%.

If there is away around this, please correct me.



*spoilers for final boss*
The final boss is pathetically easy up to this point if you have been collecting your power ups. Basically, the game informs you that nothing short of a nuclear blast can harm it. So what do you do? Hit it with a nuclear blast. There are three stations at which you can do so, the first being right in front of you. It will prompt you to press B, arming the missile, then you must use the nearby targeting system to aim at the gunship in the sky. You will do a third of its life. The next silo is to the right, then the third is over the cabin, on the other side. Rinse and repeat.

Another thing is, you will have every enemy in the game firing at you, including the attack helicopter, that spider thing, and the walker. So if you haven't picked up many armour upgrades, you're going to need to play it safe. It is advised to play on casual when going for the 'Minimalist' achievement due to this.