Well, you don't really need a pve build for bid4, you can go also with a PvP build.. So a turtle, crane or another aoe class can kill mobs at the beginning of the dungeon and you just need to auto attack the kraken with speed weapons and hold the aggro. For hold aggro I suggest use min 24% speed weapons and 5% speed hat. About the gear the best is mudosa mdef, usually I use jacket lp%, pants lp% and boots con. Antipoison necklace helps and props earrings/rings too for more damage and better defense.
When you will learn the right position to fight the kraken that will be easy to beat. Good luck with drops!
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