Charlie Murder

Team attacks are a skill that none of the characters have when beginning the game, and must be unlocked ( when you have skill points to use). Fortunately, every character's team attack is available at level 2, though most of them have different names:

Charlie and Kelly: Mosh Pit
Lester: Stygian Beast
Tommy: Gerudo Mech
Rex: Free Ride Combo

To perform a team attack, you must get a 20x hit combo without receiving a hit, which is a lot harder than it may sound in most circumstances. However, there is an extremely simple way to get a 20x combo without any enemies on screen: beat up your coop buddies! If you unequip your gloves and your coop partner is a similar level, you can beat up your buddy at least long enough to get a 20x combo to start a team attack.

Once you reach a 20x combo, simply stop attacking and an + prompt will appear below your character's health bar/photo on the screen. The prompt will remain there forever until you use it and will not go away until it is used to successfully trigger a team attack, so do not concern yourself with firing it off right away or if the other player(s) don't hop on the bandwagon the first time you hit the buttons. Hit +, and at least one coop buddy must also hit + within 3 seconds. Simply repeat as required so each person "hosts" a team attack.

This is also easily done with other controllers in a local game if you wish, and does not have to be done on Xbox Live coop. However, you will need a second gamertag.

Once you level up to about level 4 you can select a skill to do a team attack. Can't do it in Single Player. I totally lied here. Pay no attention to that and grab a friend. Thanks to ponypo2001, CheneyHeadshot & MrBojeezy. To activate it, get a 20 hit combo and press RT and LT at the same time, the have your co-op partner do the same. Join his team attack and it should pop once you've both done it.