Ok this deck is 🔥. I don't have the ultimate nightmare but it is kinda useless anyway since you can not use it for the combo with the Phoenix. It is a pain to summon yubel and Phoenix fast enough
Destroy it with yakhsa: you have to have yakhsa on the field and yubel in the hand. What then? You get terror on the field but without a Phoenix for support your basicly just stalling the duel. If you want to summon Phoenix you have to summon another yakhsa and without island on field since it will destroy terror...
there is card of soul and skill my name is yubel or u can use restart instead. and yup u can just stall until u got another combo but yubel 2 in the field its already an advantage moreover when yubel 3 is release
the combo is to destroy pheonix with island while you have yubel in hand then search for yaksha and destroy her with that. destroying yubel with fire king island is best only if you need the quick board clear