Warning: This is a very thematic and casual deck!
The whole deck has been built around the Ultimate Horror and its legions. The idea is to summon the Ultimate Horror, and your opponent will instantly freeze and lose the game. The Ultimate Horror is like a peacock from hell... it's a creature summoned from the void that has at least 27 faces on its body and wings, and any Avatar or mortal will instantly lose their mind to it.
Since this deck is designed with the theme of horrors, there is no consistent strategy other than being a midrange (late-game) deck that wins with... the ULTIMATE HORROR and lots of sparks.
All the minions (with the exception of the Castle Haunt and Nightmare, which are also horrible minions...) have VOIDWALK. Use that in the early game to tactically attack the opponent and take out minions. There is a lot of mobility in this deck since a good number of them have Airborne and extra movement.
Bottomless Pit 1, Edge of the World 2, Great Wall 1 and Mountain Pass 3 have been chosen based on the theme rather than efficiency, to create impassable or safe terrain to slow your opponent's advance, if any. Windblast and Whirlwind can be used creatively to delay the movement of your opponent minions or reposition yours as needed, remember rules about regions and that void is not affected.
Arcane Barrage works well Mix Aer and Merlins Tower to burst magic damage.
Astral Alcazar can be used as a defensive gate to return home to defend.
Peregrine Apparition and Peregrine Apparition are defensive high mobile chump blockers.
I'm not completely sure if Avatar of Air is better than Sorcerer, but if you don't have a AoA you can use a Sorcered...