Gears of War/Enemies

There are not many different enemies in the game, and the few that there are are not easily classified. After experiencing these enemies many times will you be able to recognize them.

Drones
Drones are the most common enemy in all of Gears of War. They usually carry the semi-automatic rifle (3-shot bursts), and do not often use anything else. They are fast and relativly smart, taking cover constantly and staying with their comrades, usually in packs of three to five. Aim for their knees and legs, it seems to be their weak spot.
 * Common in all acts

Scouts
Scouts are the same as drones, except that they are the ones that try to get closer to you than Drones, who usually lay back and provide cover fire, or they use the Scouts as distractions for them to flank. They carry semi-autos, and sometimes use grenades. Scouts sometimes attack you in groups of 2s and 3s, so take caution when facing them with a pistol. Same as the Drone, aim for the legs.
 * Common in all acts

Snipers
Snipers are the one who stay waaaay back, shooting you while you try to take down the comrades that are firing at you from closer up. Unlike their name, Snipers do not only use the Longshot, they also occasionally use the Torque Bow or a Lancer assaulter. Don't worry too much about these guys, since there are usually only one each per area, and they rarely fire. They try to conserve their ammo. When they have a Longshot, you have to be careful, because they shoot you at the perfect times, and you can easily die.
 * Common in acts 2-5

Grenadiers
Grenadiers are the big guys of the Locust Horde, some of the most brutal fighters bred in the Hollow. They are slightly taller than Drones, and much more aggresive. They have thick, white skin, which makes them harder to kill. They also have thick skulls, so don't rely on a one-shot headshot kill all the time, even with the Longshot. They usually carry the Lancer, but they also rush up with the shotgun and try to blow you apart. They are usually slower when in this 'rush' mode though, so you have more of a chance of getting the hell away from them.
 * Uncommon in all acts

Theron Guards
Theron Guards are souped-up Drones, the only difference being that they use the Torque Bow more often than any other weapon. They have more armour, so it takes more shots to take them down. They are easily recognizable because they have a cape that is always flapping for some reason.
 * Common in acts 3-5

Theron Sentinel
The Theron Sentinel is a high ranking Theron Guard. He carries Torque Bow, Boltok pistol and sometimes carries a Lancer assault rifle. It looks exactly the same as the Theron Guard, except for the helmet; instead of having a helmet with four eye-holes, he has a helmet with a futuristic looking visor.

Unknown Theron
The Unknown Theron is a variant of the Theron Guard/Sentinel. He is first encountered in act 4. He wears a helmet with three arrows pointing down.

Unmasked Theron
The Unmasked Theron is a variant of the Theron Guard/Sentinel. He is exactly the same as the other Therons but he doesn't wears helmet. They appear at the end of act 3, where Raam executes a Red Shirt, they're the ones who hold him. They're also the ones who ride Reavers in act 5.

The Kryll
These bat-like Locust are indestructible. The only way to avoid them is to stay in the light at all times. If you leave the light, they swarm you in about 3 seconds. No other info can be obtained on these enemies.
 * Act 2 only

Boomers
Boomers are the only enemies that carry the Boomshot, true to their name. They have incredibly thick skin and skulls, therefore making them very hard to kill. It takes a few rounds from the Lancer to take them down, any other weapon takes a lot of shots. The only way to evade Boomers is to stay the hell down. Boomers say a distinct "Boom!" before firing a rocket, afterwards taking a long time to reload. While they reload, you have ample time to put a round or two into their heads.
 * Semi-common in all acts

The Nemacyst
The Nemacyst are basically flying squids that try to fly and crash into you so that they can squirt their ink-like acid all over you. As they fly, they leave a distinct trail of dark acid, so watch out for it. To defeat them, you just have to shoot them down. They are always in packs of at least 3. It is the smallest number sighted at a time so far. (edit if you've seen more)
 * Uncommon in later acts

Berserkers
These enemies are a total pain to fight, since they are completely indestructible because of their thick, rock-like skin. They are always female, Boomers seem to be their male counterparts. The Berserker is blind, so she relies on sound and smell to track you down. To betray these senses, stay out of nose-shot, and always walk slowly if you do not want to be detected. The only way to kill these brutes is too shoot them with the Hammer of Dawn a few times.
 * Once in act 1,4, and 5

Wretches/Dark Wretches
Wretches are like mini Berserkers, except for the fact that you can blow them away with any gun you see fit. The just run along the ground, ceiling, or wall towards you, and then they just constantly jump up and slash at you. They are very easy to kill, just melee attack them with anything except the Lancer, because of it's slow chainsaw, or shoot them. The only difference between Dark and normal Wretches is that the Dark ones explode after they die.
 * Common in all acts

Reaver
The Reaver is a large, squid-like beast, resembling the "Sentinel" from the Matrix films. They are very fast and large, and almost always have a few Drones riding on them as firing platforms. They are easily defeated by either killing the drone pilots or by using the chainguns found atop the train.

Corpser
The Corpser is a giant spider-like Locust. It is the boss in Act 3. To kill the Corpser, wait for it to raise it's legs to attack. Either retreat out of the way, or roll next to one of the legs that are still down. Start shooting at the belly, and then at the chin. Repeat a few times, and then get it to try and attack you on the clamps.
 * Boss act 3

General RAAM
Finally, the last boss in the game. I won't spoil your fun on killing him, but I will describe what he does and what he looks like (don't despair, it's really easy to kill him). He walks around, carrying a giant double-barrel machine gun that looks very much like a Troika turret. He walks very slowly, shooting the whole time. He has a swarm of Kryll with him. When he is walking and shooting, the Kryll are flying around, making it harder for you to see and shoot RAAM. When RAAM stops to reaload, the Kryll form an impenetrable shield around RAAM. A powerful shot from a certain few weapons (cough,cough,sniper,cough,cough,rocket) will dispense the shield. General RAAMS's appearance is very similar to the appearance of a Boomer and Theron Guard. He wears the long cloak/cape thing, and he has very white and thick skin. His armour is red and black.
 * Final boss