The Ragnarok Enchant Deadly Poison or the EDP makes the assassin so strong. Dual daggers have already dominated the War of Emperium. A well buffed Ragnarok assassin could even destroy the emperium for a merely 6 seconds. For the EDP skill to work, it requires a Deadly Potion Bottle. It requires a lot of ingredients to make but it is all worth it. Other merchants even sell these potions.
These are the requirements to make a Deadly Potion Bottle.