Fast travel to Old Haven and follow the left wall after you get in to reach a pile of dead bandits. Notice the glowing bandit or glowing key nearby that starts the quest.
"Green Thumb" quest
To get the Green Thumb quest, fast travel to the Middle of Nowhere Bounty Board. Get a car from Scooter's and drive to the right. Notice the small shack with big plants around it. Talk to the man leaning against the shack tp get the quest.
Completion bonus
Successfully complete the game to unlock New Game+ mode. In your second session, all the enemies will be very powerful.
Critical hits
To score a critical hit on a human, shoot it in the head. With a sniper rifle this usually kills instantly For a Skag, shoot it in the face when its mouth is open. This varies depending on the type. For the pups, shoot them while they roar at you. For adults, quickly shoot them while they jump at you. For the spitters, shoot their mouths while they fire their poison projectile at you. Critical hits are easiest at close range with a shotgun or scattergun.
Duplicate item
Start a Co-op mode game. After finding a desired item, drop it on the ground then exit the game without saving it. Have your Co-op partner take the item. Resume the game and you will still see that item on the ground and can collect it. Your Co-op partner can then give you the duplicate item that was previously picked up. This can be repeated as many times as desired.
Easy experience
At the start of the game, unlock the cars then just run everyone over. The rocket launcher car is recommended; if need be you can use the rockets to kill the flying things.
Easy experience and weapon proficiency
Use the following trick to get easy experience and weapon proficiencies, as well as more weapons and cash by selling loot from all the dead enemies. For this to work, make sure you do not kill everyone. Leave one enemy alive (preferably the little ones), otherwise the quest ends. Also, do not die. You will lose lots of your hard earned money. Exit out (the game saves automatically) after killing almost all of the enemies and collecting all the sellable items desired. Reload your game and re-rampage in the arena. When you exit, the game saves all your information. Reload your game. Once you are in "the middle of nowhere" you will eventually get a Thunderdome/Arena type quest called "Circle Of Slaughter". You can go into the game, enter the arena, and slaughter everyone except one enemy. Note: There are three rounds, with the last one called" Final Round". Do not finish it if you want to repeat your work. You will earn easy experience, weapons proficiency, find nice loot, and money from selling all the items you do not want.
Easy money and experience
During the tour with the scrap robot after first starting the game, follow it to the small campsite with the raised car next to some burning tires. Collect all the guns and money along the way and kill all enemies. Then, pause game play and select "Exit". Your character will be saved with the current items and experience. Load the saved game to start at the very beginning again. Repeat this as many times as desired.
Extra item space
Create a new "bank" character for use in Co-op mode. When you want to store an item, start a Co-op game with your main character and the "bank" character. Transfer the items to be stored to the "bank" character until you need them, then transfer them back.
Hidden weapon chest and money crates
When you get off the bus at the beginning, look to your left past the claptrap. You will see a broken down gas station. When you can move, inspect the building for several money crates. Jump on top of the building to find a weapon chest.
Invincibility
Note: This procedure involves editing a game file; create a backup copy of the file before proceeding. Use a text editor to edit the "WillowGame.ini" file in the "\My Documents\My Games\Borderlands\WillowGame\Config" directory. Change the value of the "bDemiGodMode" line to "bDemiGodMode=true". Although you can still take damage, you will not go below 1 point of health.
New Haven: Hidden house with Rider gun
When you obtain (do not complete) the quest "Another Piece Of The Puzzle", you can enter a blue house in New Haven. An elevator door opens up, leading to random loot, level 30 Raider Mutants, and always one of the weapons is a gun named "Rider". Its stats usually vary slightly each time you get one. The weapon is only located in this house. The weapon's "manufacturer" is "Gearbox" (the game's developer), as opposed to an in-game company such as Dahl, Hyperion, etc. Note: When this location is used with the others in New Haven for the "Unlimited guns and money" trick, it really pays off.
New Haven: Secret vendor
Notice the garage door across from the normal weapons vendor in New Haven. There is a hidden vendor behind it. To get the door to open, try fast travelling to the gun machines in New Haven, Rust Commons West, and Middle of Nowhere. Return to New Haven and the garage door might be open.
Programmer messages
Examine the wall in the cell that Tannis is trapped inside.
Pulp Fiction reference
The names of the ships in "That Sinking Feeling" mission are Righteous Man, Great Vengeance, and Furious Anger. Each of those names is found in the biblical lines quoted by Samuel L. Jackson's character in Pulp Fiction.
Treacher's Landing: Barrel scene
Go to Treacher's Landing, then the secret dock in the southeast. Shoot the yellow barrel to the right of the dock. Then, shoot the green barrel in the far trash pile to the east of the boat. Shoot one of the blue barrels on the boat. Finally, shoot the red barrel in the water to the left of the boat.
Unlimited guns and money
Find a respawning weapons case. For example, in New Haven, there are five weapon crates that respawn every time you load the game. Three are on the roofs (above the truck stop, west staircase over the bar, and above the west gate -- jump from canopy). The repaired claptrap opens another crate behind some steel plates, and there is one more weapon crate north east behind a junk hill under a large canvas canopy. Note: There are a few bandits and aliens that spawn here. Collect the contents of the crates, quit the game, resume and collect them again. Repeat this until you get your desired weapon and sell the excess guns to get as much money as desired.
