You can target 1 Level 5 or higher Fiend monster in your GY; discard 1 Fiend monster, and if you do, Special Summon the targeted monster. You can only use this effect of "Call of the Archfiend" once per turn.
Can discard any Fiend-type monster to Special Summon 1 level 5 or higher Fiend-type monster from your Graveyard.
Continuous Trap card may clog your Field.
Being able to Special Summon high level Fiend-type monsters gives you a huge firepower advantage on the Field.
If you are using Archfiend Emperor, The First Lord of Horror, you can discard a lower level “Archfiend” monster to Special Summon Archfiend Emperor, The First Lord of Horror, and banish that “Archfiend” monster in order for Archfiend Emperor to destroy 1 card on the Field.
If you are playing other Archfiend monsters like Imprisoned Queen Archfiend, it is suggested you have Pandemonium Field Spell ready to avoid Life Point cost.
Just sharing, when I first unlocked yubel I used yami archfiend deck to farm skills. Not the best deck but slightly better than traditional archfiend (I love deck building so I got different build of multiple deck).
The combination means more draw power than normal AF and you can dump anycard you want in grave