Below i explained my reason for having each card in my deck so you can see how im thinking & can offer any advice or changes i need to make to my thought process when it comes to MTG to become a better deck builder & a better player. Thank you for your time, I appreciate it.
Why It's in the deck-
Akromas Memorial- because of all the effects it gives all of the creatures & the protections
Champion of stray souls- its mana abilities
Champion of the perished- it's active ability
Dark Ritual- to get as much mana as quickly as possible
Death Baron- the buffs it gives to all other zombies & skeletons
Grave titan- a tank that can produce zombie tokens at a decent rate
Helm of the host- apply to any of the buff givers to stack the buffs
Invoke Despair- a nice clean up card that isn't a board wipe
Killing wave- Enemy creature wipe, plain & simple
Liliana, Dreadhorde General- her abilities are great for this deck
Liliana, The Last Hope- abilities also compliment this deck well
Lord of the undead- buffs zombies & can put them back into your hand if destroyed
Mikaeus, the unhallowed- buffs everything & destroys anything that does damage to you & that's only half of it. Must have for a zombie deck in my opinion
Relentless dead- it's ability to put itself back in your hand & another zombie onto the field.
Sheoldred, the Whispering one- good way to keep opponents creature count in check.
