Hi, alright so this is a multiplayer deck revolving around reassembling skeleton mainly, it's very fun to play, there's lots of cool synergy and interactions. I've just got back into MTG and this deck is a couple of years old, i would like advice on what to change/improve if you guys can think of cool cards to add/change, cause i'm sure there's lots of black cards i don't know about.

Stuff i can do with the skeleton: sac it to sarkhan for a dragon, skullclamp it to draw, sac it to bloodthrone/fallen angel,sac it to attrition and it give you relentless blocking. Grave Pact adds value to all of those as well.

Running 4 Persecutors gives lots of synergy/meaning for others cards like sarkhan, gatekeeper, blasphemous, bloodthrone/fallen angel, attrition, fling, consuming vapors.

Mark of Mutiny is obviously very good cause you steal their best dude, attack them with it and can either sac it to sarkhan to gain a dragon or to bloodthrone/fallen angel, attrition or fling.

Now there's 3 card i feel that don't really fit the theme, they're the 2 doom blades and the crystal ball, i'm convinced the only reason why i was playing crystal ball is because it's foil lol -> I'm sure there's better cards out there but i'm clueless. Help me out!