The Hardened perk in Call of Duty: Black Ops for the PS3, Xbox 360, Wii, and PC is a perk that makes your bullets penetrate walls and objects better to kill your enemy on the other side.
Hardened Pro gives you the added benefit of doing more damage to aircraft and turrets with your guns, but more importantly it also keeps you from flinching so much when you get shot. This doesn’t sound like much, but it can be the difference between life and death in a one on one fight since you can keep your aim better while being shot than they can.
Don’t forget that you need to purchase the Hardened Pro perk upgrade after it’s unlocked for 3,000 COD points.
Here is the list of challenges for the Hardened Pro perk upgrade, and a few tips on how to get them.
Bullets in Aircraft — Shoot 200 bullets into enemy aircraft
It sounds like a lot of bullets, but it doesn’t really take all that long if you play a few games and focus on shooting a lot of bullets at some aircraft. Your teammates might not appreciate it, so don’t overdo it. If you don’t want to tick your team off, wait until you have a comfortable lead and equip a full auto machine gun to let off a bunch of rounds. If you want an easy target, lay off some rounds into the large Chinooks as they’re dropping off care packages.
Equipment Shot — Destroy 1 piece of enemy equipment through a wall
This is easier if you equip the Hacker perk. You’ll probably find a Claymore right around a corner that you can shoot through the wall. I did this one completely by accident, so it shouldn’t be that big of a deal.
Penetration Kills — Get 10 kills using Hardened and shooting through walls
See a guy in a window? Shoot at his body through the wall instead of shooting what’s peaking out. If someone is running from you, keep shooting at them through the walls where you think they’ll be running. The IR scope can help with this too, to take out unsuspecting victims through the walls. Easier in maps like Firing Range where you know your bullets will penetrate.