Kill the Slug Boss with more than 50% shield strength remaining

When you get to the Slug Boss, the one that's covering up the Array. Right before you get on the gun, go to the save point so you can restart if you mess up. After you've saved, as soon as you get on the gun and start shooting, aim for the middle left tentacle. Press RT and LT at the same time really fast, but don't overheat the guns. You should be able to kill it pretty fast. After that, take your time. Don't let the shields go underneath 50% and if you mess up, just quit and load again.

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