Many already know, but for those who don't, on Wednesday, July 23, 2025, all worlds received the World Raid featuring the Nemesis boss Sir Leopold. This raid takes place within the Book World (a new area added in the Summer Update 2025), located north of floor -3 behind a wall that only disappears when the raid occurs.
On this day, he remained alive and active from the server save until his death. He didn't disappear. In my world, we killed him 9 hours after the server save, and I believe he can be killed until the next server save, similar to bosses like Morshabaal and Gaz'Haragoth.
The remaining questions are:
1) Is there a specific day of the month for his raid to take place? For example, the 23rd of every month, like Feroxa?
2) If the day isn't fixed, did he appear in all worlds because Cipsoft "activated" him on that day?
3) Will all worlds continue to receive it on the same day, or will it appear randomly?
I'm eagerly awaiting to learn more about how this boss works so I can secure another boss in my bosstiary collection 