Welcome to Librarium Online!
I have had trouble beating the new orks lately with my necron army. even when i take alot of destroyers there is simply not enough shots in my army to come close to killing everything(at 1500, 3 mobs of 30, Ghasgull, few squads of truk boys) also my warriors and immortals saw trouble when i was being charged from truck boys that started the turn 26'' away with Ghasgull's Waagh!
how have others delt with the green horde?
I actually played the orcs recently and all I can really reccomend is to keep your distance and have cover whenever possible in case they do get to you. I would also reccomend taking out the shok attak gun (if they are using it) ASAP... also, I managed to destroy most of their armor with scarab swarms equipped with disrup. fields, so you could try that...
So... if I gave some daemons a matte paint-job, would they be "Matte Daemons?"
Necron Tactica: Flying Circus
Monolith? Just DS it, Gauss flux arc all the Green, and then portal your troops out of combat!
like Phoenix said, use a monolith...also increase your necrons so phase out isn't as big a factor.
And watch out for the burna-boy power-weapons.
"Orcs are what happens when Teenage Mutant Ninja Turtles grow old and bitter."
Monolith and alot of Immortals.
Immortals can get more shots off than destroyers, and still keep fairly mobile, some wraiths might be a good punch once a monolith DS in.
I love it when my friend tries to fire 10 rockets at my Monolith and only a couple hit, and if he's lucky one might just glance.
Kill as many as you can in shooting and when they get into combat, teleport your unit out using the Monolith and you can get the WBB reroll, then you get to rapid fire again.
If they isn't your style a C'tan can hold up a whole lot of Orcs if the don't have the strength to wound him.
I don't like Wraith so much versus Orcs as against stanard infantry they arn't playing to thier strengths and their defensive stats are only the same as a standard warrior but the cost more and have a low unit size. If you use them you'll have to be going after a small specialised unit.
You could try a large amount of Scarabs and maybe a Lord with Lightning field, that'd be funny.