Items, NPCs, quests, objects and spells of patch 1.12.1, read live from the realm itself.

Miners' Union Card

NPC	Level	Zone	Chance
Skeletal Miner Elite	17 - 18	Westfall	100%
Undead Excavator Elite	17 - 18	Westfall	100%
Undead Dynamiter Elite	17 - 18	Westfall	100%