Notes & Combos
This is a build I've climbed to Master V with; it attempts to play both Fiendsmith and Vaalmonica equally to play a strong control game. Zebufera protects the board from destruction while also allowing you to use Followed Rhythm's removal multiple times in a turn while the Fiendsmith half of the deck further attempts to deny the opponent resources.
Ideally you see a Fiendsmith card in the opener as those allow you to insulate your plays early, but even without, you can very easily pivot into the Fiendsmith side later in the turn after doing the Vaalmonica plays. Lacrima and Lurrie especially feel like better normal summons than Selettrice at times because they can more easily bait hand traps and interactions in a way that doesn't end your turn immediately, so as long as you can make it to Sequence to fuse into Duke of Demise, you can get the extra normal summon for Selettrice then and really kick off the Vaalmonica plays. The ideal endboard is Zebufera, SP and Caesar, with some way of special summoning Lacrima from GY on the opponent's turn to send Paradise to GY.
Replays
Fiendsmith Vaalmonica vs Fiendsmith Azamina Snake-Eyes
Fiendsmith Vaalmonica vs Primite Blue-Eyes