This is easily done by just playing on the first level with fists pumping. Just go through with your fists out and punch any aliens you see. You'll get it really quickly. This must be done in the campaign.

For this, you have to kill 77 Bobs. Those are the guys that are helping you, usually, at the beginning of a level. Just play the first level and kill a bunch. Then die and respawn and do it all over again until you recieve this. Thanks to Six to Eight for the info. Note that this must be done in one playthrough.

Just beat the level "6000 Feet Under" on Citadel. You will receive the achievement upon completion. This can be done in Co-op over XBL.

Just like it says, beat the single player game. It doesn't matter what difficulty.

The Tozt-7 is the flamethrower. To get this easily just sign in a guest and start a split-screen match. Set the weapon to Flamethrowers Only and first to 20 kills wins. Just go around the map and roast your guest account 20 times and you should get the achievement when the postgame lobby shows up.

Just go into Xbox Live, play a match, and of course, win. Or you can invite a friend and just have them let you win. You can even just play a split-screen match and beat your guest.

Once again, sign in a guest and start a split-screen game. Set the map to Lack of Vision, set the weapons to Fusion Pistol Only, and start the game. Have the guest account get the fuzzy ball to make them 'Invincible', then just shoot them with the Fusion Pistol a couple of times and you should get it right then and there.

See "Tastes Like Chicken". But instead of Flamethrowers Only, set it to Rocket Launchers Only.

Just go through the single player game on the easiest difficulty and you should find it very early on. About after the first level...

It's funner, and probably easier, if done in co-op. (Should also take a only a couple hours if you have already played through the game)

If you do this in co-op, you may choose to start from Level 18 - The Big House - and finish up through Level 28.

All bobs, aside from evil bobs, have to be dead upon level completion. If they teleport out, that's still fine.

Every switch needs to be either A) Punched with fist, B) Shot with Assault Rifle's Grenade, or C) Shot with fusion pistol. DO NOT USE/ACTIVE THEM NORMALY, NEVER EVER. To press  is not to punch.

And of course, just beat it on Total Carnage. After all this, you will get a neat gamerpic. Thanks to Six to Eight for that.

This is a viral achievement. One person started with it and it has spread from there. To get it you must kill someone who has the achievement. Just play some xbox live games and you'll get it. You don't have to win. You'll get the achievement in the post-game lobby. This can be done in private or player match. If you're in a hurry, you can also check out the achievement trading thread HERE to try and find someone who will let you kill them, so you can get the achievement.

Kill a Juggernaut while in Survival mode. To get to Survival mode go to Single Player and select Survival. Juggernauts should begin to spawn about 18 minutes into the game and once it does you need to kill it. Once it is dead it will start a self destruct sequence so you need to stay away from it. The juggernaut is like an upgraded drone (those flying robots that shoot green lasers). It flies and shoots fire balls and heat-seeking missiles. Click Here for a screenshot of the juggernaut.

- Run around the level before any enemies spawn gathering weapons and ammo. That way you won't have an auto-pickup screw you up later.
- Circle-strafe a lot and don't stand still much. The times I died were because I got stuck on something and then got killed.
- There are 4 health spawns, and I think the Juggernaut shows up after the third health spawn.
- Try to get enemies to fight each other and group up. Then hit them with the rocket launcher.
- Some levels are easier to navigate than others. Find one that works for you and restart until you get the one you want
- An easy way to kill the juggernaut is to shoot dual shotguns into his back (thanks Kaji)

IMPORTANT: You must go to Help & Options --> Settings --> Content Packs and select Jjaro Netmap Pack in order to be able unlock this achievement.

Win a King of The Hill or Kill The Man With The Ball game (Split-Screen, System Link or Xbox Live) and get more time with the ball/in the hill than all your opponent's times added together.

NOTE: You can give yourself this achievement by signing in three guests and starting either a KOTH or KTMWTB split-screen game. When the game starts go to the hill/ball and just hold it/stand in the hill for a few seconds. To pick up the ball you simply have to walk over it. Then end the game and you should get the achievement.

IMPORTANT: You must go to Help & Options --> Settings --> Content Packs and select Jjaro Netmap Pack in order to be able unlock this achievement. (Thanks Odysseus123)

Win at least 1 game (any gametype) on each map in the Total Carnage Netmap Pack. Each game must have at least 4 players (this can be you plus 3 guests). The fastest gametype is a Deathmatch with the kill limit set to 5. Just go around the map and kill your guests (or friends if you don't have enough controllers).

There are 12 maps in the Total Carnage Pack: Fortress Lh'owon, Melatonin, reverof nohtaram, Delusions of Grandeur, Thick and Chunky, Return to Waldo, Beyond Thunderdome, Carnage Palace Deeee-Luxe, Wrath No More?, Duality, Mime Target and You don't need to see my I.D.

IMPORTANT: You must go to Help & Options --> Settings --> Content Packs and select Total Carnage Netmap Pack in order to be able unlock this achievement and to be able to play on the maps.