My Necro build is a Zombie tribal
An imminently sensible build of how the Zombies seem to have been designed to be played.
Obvious interactions (I suspect not all of them work) include...
Crawlers + Shaggoth + maybe Ziggurat vs. swarm + Ghoul cleaner
Sacrificial Altar + Eternal Plague Servant + Graveyard (too slow?)
Idol + Gas Cloud + Cheetah Malacoda + Animate + Deathlock
Frenzy (full) or Force Wave + lots of Zombies (Brutes to hinder!)
Just one very minor quibble...
I make use of my Plague Zombies as mini tanks on guard
Pest Guards can be ignored.
Also this build is at a disadvantage vs. nonliving (Golems, Oozes, Skeleton reconstruction/pop-up archers).
I also don't fancy it against Elite flyers, mana denial and all the usual Necromancer silver bullets.
For more consistency, you may think about shoring up the weaknesses at the expense of its purist theme.
For example 1 Gas Cloud for 4 is sufficient, ideally on a Lair or Gate, Malacoda/Knight guards Idol/Deathlock.
You use the word "tribal" revealing your Magic background (Lorwyn block and predecessor Onslaught block).
With those Magic blocks, building decks was like "building by numbers" as the synergies were just spelt out.
Mage Wars with its pick mechanic is far more sophisticated; having the right tool for the right occasion is far more valuable.
This is an interesting digression on the Focus vs. Versatility axis in the game which is rarely discussed.
Playing multiple copies of the same synergetic spells gives you Focus but at the expense of Versatility.
Where you pitch your camp is really a matter of personal style.
But if you want a book that's consistently good against all opposition, you need to have some Versatility.
Otherwise you're playing "match-up lottery", beaten by some nemesis builds and walking over others.
In case this sounds negative, I really like the religious adherence to theme and synergies in your build.
I am sure it can overwhelm many builds.
Just be aware such sweeping victories is a sign of "win more" and it's better to have a higher win rate.
Yes, it means compromising the purist idea to fit solutions to lessen bad match-ups; culling always hurts.
