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An eldar from my gaming club has his mind set on playing a 500 point battle versus my 'nids.
My knowledge on eldar is somewhat limited, but I heard he's plannig something along these lines:
2 units with a starcannon weapon platform each
Any tips? try to enforce a 40k in 40mins game? or is this simply a lost cause?
That's gonna be most of his army (i am an eldar dude, i know), but there's gonna be some other troops, (an aspect warrior squad possibly).
Wraithlord's and Avatar's are daemons in close combat (not literally, but you know what i mean). So i recommend a Tyrant with Guard (expensive but they do so much damage) OR old-1-eye (coz he lives for long time)
I recommend lots of CC attacks, as Eldar troops aren't very durable. and for the Avatar/wraithlord, A decent Carnifex or even better; a tyrant with guard. Trust me on this. I know eldar and nids, but i love a good nid rampage.
Take out or weaken the Wraithlord with ranged weapons (HT Venom cannon?) as that is the strongest and toughest and smash the tyrant into the Avatar, with Gaunts ramming the infantry in CC. It will require a fair bit of luck, but the dice will be on your side if your force mostly survives the first few turns.
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I would enforce Patrol restrictions as a primary method of limiting his unit choice.
Otherwise, his choices aren't that good against Gaunts... Swarming them will keep the Avatar and WL from doing anything useful, and those same Gaunts can overwhelm and kill any regular Eldars he fields.
The Avatar is easily killed even in CC by a Tyrant, especially with ImpAtt... Though softening it up a bit will do good.
Wraithlord should be weakened at range, as said, and then killed either at range or by 'Stealers. Don't send Your Tyrant against the WL!
Normal Eldar troops shouldn't cause You too many problems if You have Gaunts to swarm them with until the TMC arrives to mutilate them.
"The meat things seek to destroy ourselves. They hunt us as we hunt them but they are weak and uncertain. The inferior flesh will be entirely destroyed, all biomatter consumed. Ourselves will fight to the last, all weak flesh must be devoured."