The Mysterious Bauble is an item that can be used from your quickbar (by right-click) in order to spawn The Great Pumpkiru. It still does so even outside of the Halloween event.
After using the Mysterious Bauble, the Great Pumpkiru will spawn close to the player character's position but not directly in front of the player character. The Bauble then has a cooldown of 30 seconds.
Please note that The Great Pumpkiru will immediately start to burn and then perish quickly if he is hit by sunlight, so you will want to use the Mysterious Bauble in a closed-up space that sunlight cannot reach.
The Bauble was implemented during the second Pumpkiru's Candy Campaign Halloween event with update R57 on October 24th 2018, and returned for the third Halloween event with update R63 on October 17th 2019.
The bauble is named "Prism" as an arc sign sprite.
How to obtain
This non-placeable block can be obtained by buying it for 1000 Pumpkiru Candy at any of the randomly spawning Pumpkirus during the annual Halloween-event that lasts for ca. three weeks around the end of October.
During the second Pumpkiru's Community Candy Campaign that started on October 24th 2018 and lasted for ca. three weeks, players could buy this item from The Great Pumpkiru or Pumpkiru Jr. for 1000 Pumpkiru Candy.
The Bauble then became tradeable again during the Halloween event 2019 that started on October 17th 2019.
The Pumpkirus will only spawn during Halloween event-times at night on solid natural blocks in dark areas on the surface of any Creativerse game world within a certain proximity around player characters, and are then indicated by a pumpkin-like symbol on the compass. When travelling the land, more Pumpkirus will spawn around players, but only during the Halloween-event-month.
Pumpkiru Candy can be collected by killing Ghost Creatures that only spawn during Halloween-event-times during ingame nights in dark areas on solid natural blocks everywhere on the surface, except for Ghost Mirus that rarely spawn in Caves at night around Halloween.
Even more Pumpkiru Candy could and still can be obtained by successfully completing Idol Events. Idol Events will immediately be initiated by placing Haunted Idols or Infused Haunted Idols or Unleashed Haunted Idol into the game world. Even though Idols could only be obtained during Pumpkiru's Community Candy Campaign, they could also be stored and thus Idol Events can still be activated by these Idols throughout the year.
However, the Pumpkiru Candy that is collected can only be traded for Halloween-themed items, rare seasonal Recipes and Costumes at Pumpkirus that will usually only appear for ca. a month around Halloween.
How to use
Since October 17th 2019, the Mysterious Bauble can be placed into your quickbar and used by clicking your right mouse button. By that, The Great Pumpkiru will immediately be summoned close to your player character (not directly in front of you though).
The Bauble then has a cooldown of 30 seconds.
Please note that the Pumpkirus will always immediately start to burst into blue flames and will then quickly vanish after they are hit by sunlight. So it is best to use the Mysterious Bauble only either in a cave or a building/room that has no windows or translucent blocks in the walls or ceiling (like slabs or tree leaves).
The Mysterious Bauble can still be used for summoning purposes even outside the Halloween event.