Allowing secondary characters ...
	Badass Rank Farming...
	Extra Wub...
	Item Duping...

When you have a character reach Tiny Tina do all of her side missions until you make it to the final stage of her tea party. Here she wants you to lure Flesh-Stick to her little cove to join her tea party. Since you can fail this mission by killing him you can actually repeat that over n over for experience. On top of that if a second controller is available and you wish to make another character but don't want to level them up the normal way you can have that created person join your session and have them run all the way to Tiny Tina. If you keep them in front of her and your main character in front of where Flesh-Stick walks out you can kill him and re-accept the mission as fast as your trigger finger allows making anyone reach roughly 20-21 in a matter of minutes.

To build a high Badass Rank, and gain all the perks associated with it, create a pair of new characters in co-op mode and have player 1 beat player 2 in 50 duels. This gives 166 Badass Ranks. Save and quit, then start another new game, creating another new character for player 1 (don't bother messing with player 2's character). Fight another 50 duels, with player 1 winning them all for 166 more Badass Ranks. Repeat as desired, and delete the pile of unwanted characters when you're done.. If you set the controller configuration to something where you can just keep tapping the melee-attack button without ruining your aim at the other player, you can finish a duel-run like this in roughly 10 minutes. Thus, over the course of one hour, you can build up 996 Badass Ranks.

To unlock extra wub, go to the title screen(where it says push start) and do the konami code, up up down down left right left right O X start. Under gameplay it will unlock extra wub, but sorry, it does literally nothing.

Get two players, then go into trade with each other. put the gun you want to trade then duel for it. Once you are into duel, drop the weapon you are trading for and let the other player pick up that weapon. Once that happens, win the duel. You win the weapon and the other player has the weapon.