When Danitha dies, Changing Loyalty triggers, returning Danitha from your graveyard to the battlefield tapped.
When Danitha enters the battlefield, it triggers, returning Changing Loyalty from your graveyard to the battlefield attached to Danitha.
Resolve the Altar of Dementia ability.
Repeat.
This clever loop uses Danitha, Benalia's Hope and Changing Loyalty to constantly cheat each other back onto the battlefield whenever Danitha hits the graveyard. While Danitha enters the battlefield to pull Changing Loyalty right back out of the graveyard and onto herself, the Aura's own resurrection effect returns Danitha whenever she is sacrificed. With Altar of Dementia acting as the ultimate sacrifice outlet fueled by this recursive engine, you can mill out any opponent's entire library in one relentless sequence.