Reload Audio Cues
When you're firing (Lancer & Hammerburst at least) and your clip starts to run low, your gun will start to make a clicking noise with every shot, that way you know to keep your eye on the ammo and start planning for a reload.
Auto-Reload Melee Trick
Sometimes during a firefight, you will inevitably stop watching your ammo level and an unexpected auto-reload will occur. If you're looking to keep your damage boost high using the active reload, this can be a real problem. The solution is to press the melee button if your active reload meter has already passed the small white zone. The reload will be canceled and as soon as you release the melee button, it will start over. This will allow you to pay more attention to the active reload meter. If your weapon isn't empty, it will just cancel the reload. However, there are 2 issues with this trick. First, it doesn't seem to work while you're taking damage and second, it will cause you to leave any cover you are behind. This isn't an issue if you are standing behind a wall, but it can be disastrous if you are crouched and it causes you to stand up.
If you are in cover, you can just switch from the current weapon that is being reloaded to a different weapon, and when you switch back to the weapon, you can start the reload with the RB (right bumper) and pay more attention. The melee trick should only be done when walking around otherwise you should switch weapons and switch back to obtain the active reload while staying in cover.
Each weapon has its own unique reloading time and active reloading point, so it's important to remember them to be ready with an active reload, even in an intense combat situation.
The torque bow has a very long reload, and the active reload is near the end, so be prepared when using it.
The boomshot and longshot have long reloads, with the longshot having a very small active reloading point.
Lancer, gnasher, and hammerburst are about average.
The snub and boltok pistols have very fast reloads.
Longshot Active Reload Tip
When you're using the Sniper, and you want the one shot down, instead of wasting your ammo until you see the enemy, waste one shot, change your gun and then when you switch back get the active reload then, alternatively, you can just press B every time it tries to reload, either way you can save a hell of a lot of ammo.
-Britainz Finest pie eater
Epic Games Forums
When faced with an enemy about 5 to 6 feet away who is about to kill you, pull out your lancer and hold forward while pressing a to barrel roll into the enemy. As soon as you come out of the roll rev your chainsaw by holding the B button. If your roll was straight you will be aligned perfectly for a chainsaw kill. (it works most of the time but sometimes if you run in to them it doesn't work). Written by: Jordn
When you're under pressure, it's sometimes best to run and head for cover. Most of the time the other team will follow you so run around a corner and keep running for a little bit, this will make them think that you're still running and not hiding on the corner so they'll blindly go around the corner, when they do this be sure to have the chainsaw out and catch them by surprise.
Chainsaw Counter Attack
If you see someone running towards you with a chainsaw, just drop a bullet in them with the lancer and their chainsaw will stop working, even better blast their face off with the shotgun.
When faced with an enemy about 5 to 6 feet away who is about to kill you, pull out your shotgun and hold forward while pressing A to barrel roll into the enemy. As soon as you come out of the roll start shooting the shotgun. If your roll was straight you will be aligned perfectly for a one shot kill. Be careful, if your opponent has seen you before you begin to roll, you may be blown to bits before you can come out of the roll, the same can happen if you miss.
When charging an enemy the best weapon of choice is generally the shotgun, the best technique to kill an opponent before he kills you is what my friends call the "Jackie". Roadie run until you are about to run into your enemy, let go of A and shoot as soon as you release the A button. You will instantly attack him. Most of the time if it is a direct "jackie" the enemy will be blown into pieces.
Firing the Shotgun from the Hip Tip
When firing the shotgun from the hip, you can use the red COG symbol which appears when you have taken damage as a reticule.
This can improve your accuracy significantly.
Easy Chainsaw+Shotgun kill
Chainsaw- When behind cover and there is someone in front of you,take out your lancer and do a cover run towards them and 1 second after running out use your chainsaw (hold B with lancer equipped)and if you do it right you will easily be able to chainsaw them instead of the worry of them shooting you.
Shotgun- When behind cover and there is someone in front of you,take out your shotgun (gnasher) and do a cover run towards them and the second you go out shoot your shotgun (press the right or R trigger) and if you do it right you should be able to kill them.
Written by: Jordn
With fragmentation grenades equipped, sneak up behind an enemy and melee. The grenade will become imbedded into their flesh and will explode approximately two seconds after sticking them. Make sure you run a safe distance away to avoid killing yourself. But of course, don't forget that you can throw grenades normally in multiplayer, too. Sometimes it's more tactical and useful to throw a grenade into a crowd than sticking one guy. Don't listen to what people say about this being cheap - it's like the chainsaw. If you let it happen to you, it's your own fault.
Defending a Grenade Tag
When you see someone running up with grenades equipped, there is a way to take them out without them tagging you. Have your Lancer Rifle equipped, and as the grenadier approaches hold B to keep the chainsaw revved. If they get too close, you will chainsaw them automatically before you are tagged. A very good tactic, but can be dangerous, as sometimes they will be able to tag you out of chainsawing distance. Usually a grenadier will simply try and catch you and won't change weapons until it is complete. Don't feel weak by getting a safe distance away and gunning them down. He can't tag you if he's dead.
NOTE: If you do get tagged, try to run into the tagger to kill him too, although you can only kill the one that tagged you, not any of the tagger's friends (if friendly fire is off). Also, if near teammates, run away from them, as an enemy grenade stuck on you can kill your allies, too. Another option is to chainsaw the tagger. It kills an enemy and when it explodes you don't die(for some odd reason you are in god mode while in the middle of chainsawing)
Skipping a cutscene
Press X in order to skip a cutscene. Scenes in-game cannot be skipped. e.g. the "we can take the safe route or go directly into action" speech at the beginning.
Take Advantage of Camera Angle
Remember that your character is right-handed and it seems that because of that the camera is friendlier to you when you go around corners going to your right instead of your left.So when you get into a gunfight with an opponent and there is an obstacle in the way, move around that obstacle by moving towards your right as the angle of the camera will help you get a cleaner shot. (Provided by BuRNouT693)
While blind fire is commonly over-looked in multi-player, it can save your neck. If you are pinned down and almost about to die simply let loose a couple rounds of whatever weapon your holding. It may delay your opponents just long enough to recover that much-needed health.
Blind fire around a corner can be more powerful than moving out to aim; however some weapons (the longshot and torque bow) aren't particularly useful for this purpose. To effectively use the torque bow from cover, hold the right trigger to charge it up, wait a second, then pop out and aim as you will have a fully charged torque bow and be able to stick one right in them!
When blind firing remember, that your head is still exposed just a bit for a sniper to shoot off.
-Jagnot -Edited by Zarthustra
Walk towards any object that you can normally jump over. Then press A+B at the same time while you are walking. You should fly over that wall and give you a little boost. Although, you can only do this when you are not host.