Borderlands 2 Color Rarity Guide
The Borderlands 2 loot engine generates all items dynamically. It doesn't just pull them from a library of pre-created gear. The names, special abilities, and statistics are all chosen this way for each item. So if you get a special shield or weapon, then it happened by chance (usually). The level of rarity the item has is also dynamically set. Note that some rare items can be worse than common items. Also note that rarer items have an increased value for selling them so if you want to make money. There are 6 colour types for the label of the weapon to be colored as. They correspond with the level of rarity
Borderlands 2 Color Rarity Scale
White (Common Item)
Green (Uncommon Item)
Blue (Rare Item)
Purple (Epic Item)
Orange (Legendary Item)
Seraph Weapons -- There are also the new SERAPH items (they aren't red by the way) and different levels of rarity for Seraph weapons.
Borderlands 2: Best Way to Get Rare Loot
Playthrough 2: During Playthrough 2, all enemies get harder. They also drop better loot, which makes the rare gear they drop even better. Item hunt during playthrough 2 instead of 1.
Vault Hunter's Relic: (VHR) This special artifact "increases the chance of rare loot dropping" by 5%. That is a small percent, but it can help! Some people say that this is a useless artifact -- as it actually just decreases the chance that WHITE gear is dropped rather then increases the percentage of rare gear being dropped...But it can help. Just don't put too much faith in it. You get this if you pre-ordered the game.
Lucrative Opportunity Artifact: There is an artifact that actually makes all the vending machines count down 24.4% faster so that you cycle through new sales faster. This can help you find great gear sometimes, but you have to be patient and keep checking when you can.
Fight Bosses: You can fight bosses in this game over and over. Fight them again (especially in Playthrough 2) several times to get rare loot!
Use Golden Keys: The golden keys you can get in this game allow you to open special rare loot chests in Sanctuary that spits out rare items. The higher your level when you open one of these special chests, the better the gear -- so use your Golden Key late in the game! Check out Borderlands 2: How to get All Golden Keys (Cheat) for information on how to get more golden keys!
Find Hidden Chests: There are lots of hidden, secret loot chests in the game. Look for them and open them to get some (possibly) nice loot.Play the Lottery: Playing the lottery can help you to get some nice loot. It can be expensive though! Be rich.
Terramorphous the Invincible: The original game - Borderlands 1 - had a big, bad, super monster available to fight on it named Crawmerax that was available through the DLC The Secret Armory of General Knoxx. This monster, though very difficult to kill, dropped truck loads of rare loot when defeated! Similarly, Borderlands 2 has Terramorphous the Invincible -- a super monster that when killed ALSO gives you extremely intense gear. He is even harder than his counterpart Crawmerax, and it costs 4 Eridium just to fight him. This is best done in a group rather than solo (duo works too), as you will need to be revived since you WILL die, though he IS solo'able. The great part about this is you can fight Terramorphous the Invincible as many times as you want. This awesome monster is located at Terramorphous Peak.
You can also trade with friends if you want to get rare loot that they may not even need. Note that being in parties with high leveled members can also help to increase the loot quality, as the monsters get harder to scale the difficulty.
Some people may even resort to using a Borderlands 2 Trainer to Hack Items and create overly powerful weapons or mod their game, which isn't something you should do if you patch your game.
Hopefully this helped you get some ideas on how to get rare loot from Borderlands 2.
Borderlands 2 Legendary Loot FAQ
In an attempt to answer questions directly, a FAQ has been opened within this section! Have questions? Comment below and they will be answered + added to the FAQ!
Q: What is the drop percentage of Legendary items?
A: It is highly variable. The percent or chance of you getting a special item is different depending on the scenario. For example, it is increased when fighting a boss as compared to fighting a regular enemy. It can also vary depending on the loot chest you open and so forth. The easiest way to raise the percentage / possibility of you getting a legendary weapon or item, is to simply use golden keys for special loot chests. Obviously this isn't something you can just do instantly unless you have golden keys or hacked them / used a trainer (see Borderlands 2: How to get All Golden Keys (Cheat)). The percentage varies for epic and rare items too, as well as E-Tech and Seraph gear.