A couple of days ago, a data miner on Reddit found several references inside the code of Diablo 3 on Switch that seemed to suggest new custom amiibo would be released for the game. Now, thanks to an official announcement from Blizzard, we know that, yes, those amiibo really are real. Hooray!
— Diablo (@Diablo) November 1, 2018
Revealed by the official Diablo Twitter account, a Loot Goblin amiibo is coming to stores this December. Referred to in the game files as 'Treasure Goblin', this seems to confirm the veracity of the leaked information. While only the Loot Goblin was announced at this time, we can likely expect a Demon amiibo as well as support for non-Diablo-themed amiibo based on the data miner's information.
The Loot Goblin will apparently "open a portal to untold riches" – which likely means it'll provide access to the Treasure Vault, but we'll have to wait and see.