Hearthpwn

I've played something similar, have 80% winrate over 40 games.

Few changes... Haunting nightmare and Ghoul is probably the biggest, they are really, really good. Ghoul + Xyrella wins the long games.

Full list: https://ibb.co/x3mYTqb

I have been running Shadow Priest with success for a while now and I noticed many of the deck creators choose minions that don't benefit the deck. With Shadow Priest you aim to close the game by turn 8 or 9 the latest. Therefore cards like Invincible and Thrive in the Shadows are not worth it. Invincible is too expensive and Thrive in the Shadows is too slow, as you need direct activity on the playground. Try replacing these cards with another ending combo like Voidtouched Attendant + Astalor Bloodsworn . The amount of times that combo gave me the win is insane. And I would add in 1 more Cathedral of Atonement for the card draw. As said, you aim to win this game by turn 8 or 9. So if you don't draw your undead's in the early turns but you do get Cathedral of Atonement , this gives you a better chance of actually drawing your undeads.

I also have 1 Spirit Guide in my list, also for the card draw mid game. 
Hope this helps tuning your deck a bit.

do you wonna share it?

hey, have been really enjoying the shadow aggro priests so far so wanted to give yours a try as well! Worked out fine for me and made a little showcase of the deck if anyone wants to see it in action! PS the second game is better

Very fun, thanks.