Require 450+ Level!
On Friday, Saturday, and Sunday at 19:55, an announcement is made that Sasuke has detected Otsutsuki chakra in the castle. At 20:00, a teleport appears on the Hokage building roof, allowing entry to the castle. A boss will spawn and may have several forms.

The top 3 damage dealers receive rewards with a bonus loot chance, and other players who dealt recent damage also receive rewards.

Otsutsuki Bosses

Bijuu	Day	Loot
Bijuu	Saturday	Toneri Sword Toneri Glove Toneri Ring Toneri Necklace
Bijuu	Friday	Kinshiki Bandana Kinshiki Armor Kinshiki Legs Kinshiki Boots
Bijuu	Sunday	Momoshiki Helmet Momoshiki Armor Momoshiki Legs Momoshiki Boots

Disclaimer:
The times shown in the table are based on server machine timezone (Europe/Warsaw (CEST, +0200)).