With Bind Demon 20+, the binded Demon will gain Aura Enchanted, with a random aura from the available ones for the affix (unless it already was Aura Enchanted in which case it keeps his previous aura)
That said, can I keep unbinding and re-binding until get a specifi aura?
(Still levelingy Warlock... so I cannot test myself yet
fredkid
1911