This Interval has 3 missions.
Urban Decay
Point of Entry Part 1
Point of Entry Part 2
Some tips I have are to use the Repeater Cannon and Trip Mines on the armored robots, and the Particle Rifle against the enemies who are using it. If you get hit with it a few times it can really mess you up. There are also a few of those Ninja type guys,(from earlier in the game, they can go invisible and really mess you up) I had the best luck with the shotgun against them. If you are having trouble with this Interval then take it slow and save your ammo for the tough armored enemies.