The Welkin Hat (also commonly referred to as Isi's Wizard Hat) is an accessory that can be worn by the player. The wizard hat is a cosmetic item which means that it will not show up in a player's inventory.
The Welkin hat can be obtained from a giveaway in the Pixelmon Discord's #all-hail-pixelbot channel, and is sometimes awarded to those who have contributed to the mod in some way. It can be activated in-game by using the command /redeem gui
and selecting it within the hat drop-down menu.
Once the hat is selected, the /redeem toggle hat
command can be used to toggle its visibility.