Use "Enemy Controller" to take control of a high-level monster on your opponent's side of the field to remove for this card, both summoning a powerful fiend monster and to get rid of a few high-level ones of your opponent's.
Use "Tragoedia" for a quick use of this card. First copy the level of the Fiend-Type monster you want to Special Summon with the second effect of "Tragoedia", and then activate this card.
Use this card on a Level 3 monster while you control another Level 3 monster. This will allow you to Xyz Summon "Leviair the Sea Dragon" with a target ready for Leviair's effect (provided there wasn't one until this move is made).