Defeat World/Field Bosses (excluding Vell) during the event period which is from November 24, 2021 (Wed) after maintenance till December 15, 2021 (Wed) before maintenance, to be 100% guaranteed to obtain [Event] Old Moon Boss Seal

It's a good opportunity to stack up Magical Shards which are needed to craft several items including the Guaranteed PEN Accessory/ Armors/Weapons and so much more, to do so, just bring the [Event] Old Moon Boss Seals to NPC Jetina (if you have no idea whereabout the NPC, you can always check it out on the '' Find NPC'' Feature) as shown below 

and exchange them for Magical Shards or whatever you want it from the following items : 

The [Event] Old Moon Boss Seal can still be exchanged after the event ends.

That's it about this guide, you can always chat/ask me anything about the game on Discord : Dustan#0325

Enjoy your time !