M4A1

The M4A1 (called the Carbine in game files) is an assault rifle that appears in BlastGen. It appears in all modes.

Campaign
The M4A1 is a common weapon in the Campaign, being the signature weapon of the Marines. A unique variant called the M4A1 SOPMOD, fitted with an ACOG Sight, Foregrip, Suppressor, and a Laser Sight is Michael Hicks's starting weapon in most missions, except for Prison Break, where he instead uses an AK-47.

Another variant of the M4A1 is the M4A1 Grenadier, which is fitted with a Reflex Sight and a M203 grenade launcher. This particular variant is used exclusively by Emerson, Vaughn, and Oscar Thomas, and thus cannot be obtained. It is a well rounded weapon, being able to kill most enemies with 2 shots at virtually any range. However, it does have visual kick when aiming, so it's recommended to hipfire often, specifically in close quarters.

Multiplayer
It is unlocked at the start, along with the Colt. It is a well rounded weapon, dealing about 40 damage per shot, resulting in a 3 shot kill. It has a 30 round magazine, carry handle iron sights, and a permanently attached vertical grip. It has a large assortment of attachments, like all assault rifles in its class. If the player dislikes the iron sights, the Reflex and Holographic Sights are available. If a player wants to engage enemies from further ranges, then they can attach the Sniper Scope. The M4A1 is a perfect weapon for new players, and is the only primary weapon the player starts with, as other rifles are unlocked much later.

Some players dislike the M4A1, and prefer to use the AK-47 once its unlocked. This is understandable, as the AK-47 deals much more damage per shot, however it has much more recoil than the M4A1, while the M4A1 has virtually no recoil whatsoever, but it does have idle sway. Sniper oriented players see this weapon as a reliable sidearm in case an enemy tries to rush them, but others prefer submachine guns or even shotguns. Nevertheless, the M4A1 is a good weapon.

Zombies
The M4A1, simply called the M4 Carbine, appears as a wall buy in the map Townhouse for 1500 points, and is available in the Strongbox on the other maps. It recycles the M4A1 model from the Campaign, and thus lacks the Foregrip the multiplayer variant has. It deals 45 damage per shot, which results in a 3 shot kill or a 1 shot kill to the head on the early rounds. However on Round 20 its effectiveness is strained, requiring at least 5 or even 7 shots to kill a zombie, even when aiming at the head. When upgraded, it becomes the Skeeter, with increased damage, a larger magazine, and gains a Holographic Sight. It remains effective even through the much later rounds, up until Round 40, where it becomes much weaker. It is the most popular assault rifle in Zombies, along with the M16 and AK-47.

Trivia

 * The word 'skeeter' is an informal term for mosquito.
 * The M4A1 has a permanently attached foregrip, but it is not held unless the Foregrip is attached.
 * The M4A1 SOPMOD's ACOG Sight in the Campaign has the zoom of a Reflex Sight.