What's the deal with the new rarity level in the Captain Scarlett DLC?

I heard Captain Scarlett and Her Pirate's Booty has a new rarity level; something pinkish? How will I recognize the new guns, and how do I find them?


It's called Seraph weapons

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and will be acquired by trading the new currency "Seraph" to a vendor in Oasis after doing Hyperius The Invincible and Master Gee The Invincible quests.

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