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+ Rez Orb
3 Heavy Destroyers
So what do you think? Usually i keep a Monolith out to deep strike in mid game and attach the lord to my immortals
With two monoliths you should have plenty of anti-tank ability via PWs. I'd suggest drop the heavy destroyers, change them to 3 standard destroyers and a third wraith.
Also if your lord is with immortals, you can swap the res orb and one immortal for a VoD. The amount of teleportation had with two monos and a Veil is on the side of excessive (but fun).
8 is on the low end for PO at 1.5k in my book
Honestly the wraiths seem somewhat out of place. Though I can't say they're a bad choice. Use them wisely, heavy weapons squads or HQs are prime targets for them. As well as monstrous creatures.
2 Liths in 1.5K, cool
Id drop the Heavies and Wraiths and get in Destroyers and Scarabs instead.
The way i see it the heavy destroyers are better suited because as an anti tank they have greater range and movement
and i also would like to keep my monoliths open to use its power matrix to teleport instead of restricted to killing the tanks
Destroyers and Heavy destroyers have the exact same range and movement.
Destroyers use Gauss so with 3 shooting you're still likely to get a glance even on high armor vehicles.
Fair on the power matrix however these ARE Necrons, you don't need high S to rip up vehicles. Destroyers are much more reliable once all the vehicles are dead and it's time to grind out the infantry.
What armies do you play against? If ya see alot of 2+ saves I'd understand using HDs over destroyers but usually the FA variation just performs better.
I play against DH, CSM, Eldar and Daemons