Grammar is important

To quote a post from a games forum,

" Capitalization can make the difference between "helping Uncle Jack off a horse" and "helping uncle jack off a horse".
A few simple caps can turn a normal situation into a scar-for-life moment.

Commas can make a huge difference too. For example: "Let's eat, Grandma!" is far different from "Let's eat Grandma!"
Commas save lives.

Using good grammar pays off in mysterious ways, people. "

Nation Red is an ultra fast infinite play arena-based shooter providing an exceptional close-quarter battlefield experience.
Fight thousands of zombie Mutants and their bosses in frantic bloody gameplay while earning over 70 perks.

August 17, 1977
Scattered groups of zombies infiltrate remote Midwestern towns.
Incapable of using tools or weapons, the invaders are resisted until they retreat back into the desert.
Special elimination posses are set Up to hunt down any of the surviving undead. Six weeks after the squads started their search-and-destroy mission, the last known zombie was shot and killed.

Present-day
over thirty years had passed when a truck driver traveling down a desolate Arizona road plows into a wall of undead.
Before the driver's phone signal went dead, he reported some were carrying guns... They're back and now they are hunting us.
Steam Exclusive Features:

Local and On-Line Coop — Take on the horde and earn perks together  
Barricade Mode — Defend your base against zombie attack  
58 Steam Achievements and a dozen Leaderboards  
30 Additional Steam User-designed Perks  
Xbox 360 Controller support for single or multiplayer  
Steam Hammer — Rips the skin off your opponent (nice)  
New Steam User designed weapons — Minigun, AA-12, MP5, Beretta 93R, Super Shorty and more  
New Level and New Enemies — Zombie patients and caretakers in a desert asylum, Brawler boss zombies,  
Suicide bomber   zombies..  
Pneumatic Destroyer — Detonates the Rammer they are surrounded by zombies   

Key Features:

Ultra Fast Action — Fight armies of hundreds of zombies and their bosses in an exceptional close-quarter battlefield   experience  
Deadly Weapons — Use machetes, axes, Jack hammers, dual Uzis, flame throwers, grenades, poison and a dozen more  
including   a Steam Hammer, exclusive to Steam purchasers  
Customize Yourself — Over 70 player modifiers combine with two dozen power-ups for limitless gameplay  
Four Game Modes — Free Play, Survival, Barricade and 18 increasingly brutal missions await    
Zombies with Guns — They wield axes, cut-off saws, AK-47s and more  

Can you find what is wrong?
Nation Red
Fix them and you will be right.