Necromancer/Monk
Preliminary Attributes:
Death Magic: 12+1+3
Soul Reaping: 12+1
Spare: 6 points
Skills:
Animate Bone Fiend
Animate Bone Horror
Blood of the Master
Aura of the Lich {E}
Contemplation of Purity
[Open]
[Open]
Resurrection Signet
Basic strategy:
This build is centered around using Aura of the Lich to allow for spamming of sacrifice skills, specifically Blood of the Master or possibly one of the two open slots. AotL is a really powerful spell that almost allows an MM to manage its own health independently. Low on health? Need a condition and/or hex removed? Cast Contemplation of Purity and you'll most likely be back at full health with fewer/no conditions and ready to keep on sacrifincing. Of course, don't forget to summon fiends and horrors all the while!
Thoughts for open slots:
-Blood Ritual (Change atts to 10+1 Soul Reaping, 9+1 Blood Magic)
-Verata's Aura (In case you're partying with a second MM who might die, or you don't trust your healers)
-Death Nova (Always a nice standby, especially if you have an A/Mo Naruto kid in your party.

-Deathly chill/swarm (straight offense not tied to minions/corpses)
-Heal Party, infuse health (hey, why not? add points to healing prayers)
-Enchantments in general (for support, and to buff your Contemplation of Purity casts)
-New build entirely. Aura of the Lich could probably be used for sacrifice-heavy support builds other than MM.
Gear: Anything works. I really like using a 20/20 wand and 20/20 offhand for that juicy 40/40 bonus.
Strengths:
-Resilience. Half-damage goes a long way, and in the face of high degen or bad healing, cancel Aura of the Lich with Contemplation of Purity to restore your health to a safe level.
-Versatility. Two open slots means you have space to support your teammates or deal more damage. Also, ample space to bring a capture signet in PvE.
Weaknesses:
-Energy. An Achilles' Heel for any MM build, this build demands a lot of energy. 4 pips of energy regen is enough to let you spam Blood of the Master to your heart's content, but for summoning you're going to have to rely on intelligent casting and Soul Reaping to keep you going.
-High degen: if you get hit with high degen, you can probably counter the worst of it when Contemplation of Purity to cancel Aura of the Lich, but if you're not paying attention the degen will wipe you out pretty quickly. Be ready to concentrate on the game while running this build.
Credit: Myself
So far, I've only used this build to faction farm the Jade Arena with henchies, a purpose for which it has worked very well.
Comments, thoughts, and criticism are all welcome.