Here are some weapon descriptions to give you an idea on what to use in combat
my basic weapon setup is the lancer, torque bow, and shotgun, to give an idea im usually a theron guard when playing locust and Dom when playing COG
Snub Pistol - the standard sidearm of the COG. Holds a 12 round clip, high rate of fire as well as accuracy, very powerful.
boltok pistol (Revolver) - standard issue sidearm of the Locust. Holds a 6 round cylinder, slow rate of fire, very powerful at close range.
There are two types of hammerburst weapons as used by the Locust
Hammerburst - early standard issue rifle for the Locust, mostly used by drones and small infantry. Holds a 78 round clip, 6 round burst fire, high accuracy with a medium to low range.
Hammerburst II - improved standard issue rifle upgraded from the early hammerburst after the light mass bomb, 17 round clip, automatic/semi-automatic with a 4 round per second as long as the trigger is pulled, high accuracy with medium range.
Gnasher Shotgun - standard shotgun for the COG, lever action with 8 shell capacity, can be extremely accurate to very inaccurate depending on the range.
Lancer Assault Rifle - standard issue assault rifle of the COG, 60 round clip, automatic 15 rounds per second, has a medium range and accuracy, attached is a chainsaw bayonet used for melee combat , very powerful on the unexpected enemy.
Longshot Sniper Rifle - High-Caliber single shot bolt action, can only hold one round at a time, slow rate of fire, very high accuracy and is very powerful.
Hammer of Dawn - the HOLY %#@^ weapon created by the COG, infinite magazine, 3 second charge with a 7 second laser burst, operated via satellite and can only be used for a short amount of time very deadly, has an instant kill effect.
Boomshot Grenade Launcher - "BOOOOOM" - Locust Boomer, very powerful grenade launcher with an instant kill if hit directly, 1 grenade round, single shot, slow rate of fire, medium accuracy.
Torque Bow - official bow of the Theron Guards, 1 imulsion-tipped bolt, charged mechanism for high accuracy but has a slow rate of fire.
Frag Grenade - aka the bolo grenade, standard grenade setup for both the COG and Locust,medium to instant kill, can be thrown, stuck to walls as a proximity and stuck to enemies with a 4 second delay.
Smoke Grenade - self explanatory, non lethel mostly used as a smoke screen blinding anyone who walks through it, useful for stealth and to move from cover without getting shot up.
Gorgon Pistol - one of the coolest auto pistols seen in GOW2, 32 round clip twin clips, 8 round burst fire, slow to high rate of fire.
Boomshield - Hells riot shield, bullet/ explosive resistent shield, melee attack, can be set anywhere and used as a portable barrier to shoot around and provide cover.
Scorcher Flamethrower - your basic flamethrower, with a 360 ammunition capacity fuel tank, short ranged combat, igniting enemies into fire.
Troika Turret - mounted machine gun, high everything, extreme damage, unlimited ammo, placed at certain spots on a map.
Mulcher - carriable machine gun, 250 max ammo, fully automatic, can be set up as a turret on any ledge, hand cranked with a high accuracy and deadly rate of fire.
Ink Grenade - like a bolo and smoke combined, when thrown or detonated, a posionous and blinding gas appears, damaging and blinding to anyone who is got in it, very good for getting out of a tough situation and getting somewhere safer.
Mortar - self explanatory, 1 round, when fired explodes launching 5 bombshells, high explosive shells, very deadly when caught in the blast.
GOW3 Weapons In progress
One Shot - Recoiless rifle,jokingly called the elephant rifle for its instant kill effect that will blow enemies apart.
Sawed-Off Shotgun - very high damage, two shot capacity, can blow multiple enemies into pieces. best effective when used at close range, long reloading process so the shot must count otherwise youll be in danger of getting shot
Retro Lancer - official standard issue rifle used during the pendulum wars, same as the lancer but more accurate, equipped with a standard knife bayonet unlike the chainsaw bayonet, the knife charge can be thrusted through the enemie for an instant kill, cannot be used to battle other bayonets like the chainsaw duels.
-bad accuracy, but very powerful, much like the hammerburst semi automatic.
should be used with short controlled burst for the best results
Digger Launcher - unique grenade launcher, fires a Digger either into an enemy or into the ground, when fired into the ground it can penetrate enemies that are hiding behind carrier, when fired into an enemy it will chew through as an instant kill, be aware of the high pitched screaming as its approaching its target.
will edit further as i find out more on the weapons