Again thanks for TOS fansite
colg.cn who created this great guide, and what I did was translated it to English. I know the second international closed beta is going to end soon but still hope this guide will help you in next beta and after formal launch.
Three things you need to know about world boss
1. World bosses usually spawn inside the common buildings of dungeons, and they have their levels.
2. To be eligible for world boss loot, you have to be in one of the 6 groups that deal most damage to the boss. In other word, you need to be in a strong group.
3. Except Durahan, all world bosses spawn 4 hours after last death but randomly in several locations in the map.
Dullahan - lvl 185
Location: Roxona Reconstruction Agency East Building
Condition: Collect 200 minions' soul with a crystal bottle spawns every 2 hours
Drop: Dullahan Armor Fragment(10%), Dullahan Card(50%), Gritas(10%),Geras Spear Recipe (10%), Karacha Dagger Recipe
Deathweaver - lvl 24
Location: Crystal Mine 2F or 3F
Drop:
Deathweaver weapons Chapparition - lvl 42
Location: Tenet Chapel basement or 1F
Drop:
Chapparition weapons (1% for each type), Sliver Bar (1%)
Abomination - lvl 56
Location: Great Woodlands
Drop:
Abomination accessories
Temple Shooter - lvl 76
Location: Royal Mausoleum Workers' Lodge
Drop: Templeshooter Card (10%),Earth Gloves (10%), Leather Earth Gloves (10%), Earth Plate Gauntlets (10%), Earth Boots (10%), Leather Earth Boots (10%), Earth Plate Greaves (10%)
Kanseril - lvl 81
Location: Royal Mausoleum Builder's Chapel
Drop: Kanseril Card (10%), Earth Pants (10%), Leather Earth Pants (10%), Earth Plate Pants (10%), Earth Robe (10%), Leather Earth Armor (10%), Earth Plate Armor (10%), Wind Runner Recipe (10%)
Earth Archon - lvl 85
Location: Royal Mausoleum Storage
Drop: Gold Bar, Maid Headband accessory, Regina Crossbow, Sapphire, Silver Bar, Toy Hammer
Cerberus - lvl 96
Location: Royal Mausoleum 4F, 5F
Drop: Cerberus Card(20%), Opal(2%), Durandal(2%), Primaluce(10%), Nurse Headband(10%), Gold Bar(10%), Gladiator Band Recipe(10%)
Noisy Mineloader - lvl 130
Location: Mage Tower 4F, 5F
Drop: Mineloader Card(15%), Pink Bunny(20%), Gold Bar(10%), Trinity Sword Recipe(10%), Wildling Bane Recipe(5%)
Necroventer - lvl 133
Location: Residence of the Fallen Legwyn Family
Drop: Legwyn Family Cloth/Leather/Plate Sets, Nulis, Petamion Recipe
Fire Lord - lvl 148
Location: The main hall of Sanctuary
Drop: Fire Lord Card(10%), Wizard Slayer Recipe(10%), Maledic(3%), Red Gem(10%), Kaloo Hammer Recipe(10%), Pumpkin Amulet(10%)
Harpia - lvl 166
Location: Demon Prison 1F, 2F, 5F
Drop: Harpia Card(10%), Luciduce Recipe(10%), Audra Recipe(10%), Zircon(10%), Skull Amulet (10%)
Glackuman - lvl 164
Location: The 2nd Demons' Prison
Drop: Nulis recipe, Miskas Sabre
Marionette - lvl 181
Location: Roxona Reconstuction Agency West Building
Drop: Marionette Card(10%), Complex gear(50%), Grave Crossbow Recipe(10%), Suncus Maul(10%), Conqueror Recipe(10%)
Starving Ellaganos - lvl 200
Location: Bidentis Shrine or Mokusul Chamber
Drop: Ellaganos Card(10%), Maledoom Recipe(10%), Max Petamion Recipe(10%), Feather Armband Recipe(10%), Sissel Bracelet Recipe(10%)