dmhenderson

You can't unless you have a mission to clear infestations and then someone will tag along automatically. The trick is to use a vehicle to paste the guys outside before you try to enter the house.

Easiest way to do it is to get someone who's proficient with a rifle and start popping the ones roaming around outside which will draw a crowd. Get back in your car and just run them all over. Wash, rinse, repeat.

After that it's only a matter of clearing the few dudes inside (usually a screamer or two).

The most important part of that game is to always carry at least 3 energy boosting items and 3 health regens and ALWAYS leave yourself an out if sh*t goes sideways.

Edit: The military chick (Marla) and Marcus are the two most well-rounded characters in the game.
Marcus gets a huge bonus to melee damage so spec him in heavy or blunt weapons and just go to town. He's the most efficient because he also gets endurance bonuses etc later on.
Marla is fantastic at sniping and the gun she comes with is one of a kind. I prefer the bolt action rifle she has at the start over the semi-autos you can get later in the game due to reload speed and recoil. Once you spec her in rifles she even gets a "bullet time" ability where you can slow time and just annihilate everything.

Either of them can take down hordes all by themselves - esp marcus once he gets his advanced melee stuff where he's piledriving/suplexing zombies all over the place. Charging into a horde of zombies with a pipe wrench and just wrecking sh*t is fun as hell.

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