Advice against chaos marines?

I've played chaos marines before, but not with my dark eldar.

What should I expect? He probably won't have a helldrake.

He tends to run nurgle/Tazeech and/or slaneesh and ally with daemons.

I got from another thread here I should bring poison incase he brings nurgle, but what about the other two? I'm confident I can dance around khorne.

I think you just told us what to expect. No Heldrakes and probably some oddball cult troop mash.

Against Nurgle: Laugh
Against Tzeentch: Also Laugh
Against Slaanesh: Beware of Blast Master

If you're playing against a bunch of Noise Marines with Icon of Excess, feel free to pick off random Noise Marines with Dark Lances (Focus Firing) to negate FNP and then use your poison weapons to crack guys in cover. Do that only if armor isn't an especially big deal.

How deadly are forgefiends?

With what setup?

Any, I havn't faced them yet, but the guy I'm going to play sometimes does if he isn't fielding defilers.

I wouldn not be afraid of Chaos Space Marines.
Its rather to remember to stay away from bolter range as they can wreck your veichles rather easy.

Their threat bubble are 24", and its easy to shoot out whatever has better range in turn 1. So target priority is rather take out first whatever has more than 24" threat bubble.

Any setup is nasty but the basic one is probably the worst case scenario for Dark Eldar. 8 BS 3 STR 8 shots with the option to get re-rolls on To Hit and Armor Penetration once per game. One round of shooting ought to inflict 2.22 Glances/Pens, 0.6 of which are explode results on an AV 10 Open Topped Skimmer with Jink. The vehicle itself is 12/12/10 with a 5+ Invulnerable Save and It Will Not Die. The price tag there is ~175.

Edit: Also, they ignore Shaken and Stunned on a 2+.

So basicly treat them like space wolves? Night shields everywhere?

What's the range on their gun? ANd I guess Ravagers to counter it? What about the voidraven bomber?

Not sure what you're referring to but the Hades Autocannon (the basic gun on the Forgefiend) has a 36" range. Nasty thing.

I fully endorse using Night Shields. They are excellent at denying First Blood, making Melta Guns useless, and generally staying out of Rapid Fire range.

My other army is CSM, and I heartily recommend Nightshields when facing them. If he has forgefiends, you've gotta lance from a distance. Don't forget those cannons are Pinning, too.
VS defilers, same plan. Lances away! I would maybe avoid trying to haywire defilers, since they've got a flamer or heavy flamer they can use for overwatch.
If he brings Maulerfiends (no shooting, anti-vehicle CC), try bog 'em down with wyches. Be careful, though, 'cause they ignore cover when moving, move 12", and basically don't care about overwatch. But they've only got so many attacks, and they're all S10/AP2 so totally wasted on wyches with their 4++. I would say MSU Haywire/Venoms is your way to go.

Marines are Marines, whether they've got T5, AP3, or Ignores Cover. As long as you stay out of bolter fire range, they're not a serious worry. Yes each squad will be bringing one long-range gun, but you know how to deal with those.

If he's allying with Daemons, cross your fingers he brings Daemon Princes. You can eat them for breakfast with poison.

Honestly, I think Ravagers, Kabbie Raiders, & Haywych Venoms are solid choices. I personally have a lot of success with wracks vs marines, but ymmv.

CSM without Helldrakes are a joke to us, just use your standard MEQ tactics and your do fine...

Well I beat him guys thanks to your advice.

He's getting helldrakes now though, how am I supposed to deal with them? I talked him out of using 3 against me, but I should expect 1-2 in 1500, 3 in 2k (not to concerned about 2k though).

I usually stay more than 36" from enemys table edge before the Helldrakes arrive to avoid vector strike and shoot his ground forces to pieces. Then when the turkies come I try to get behind them to again avoid vector strikes. If Helldrakes hovers it dies to lances or Haywire grenades. MSU helps here as they can only effect one unit at the time.

Doesn't that leave you penned in your own deployment zone for at least 2-3 turns every battle? I f I was facing a DE army that did that I'd be delighted. Knock out your AT and stay in my transports in perfect safety until the Helldrakes come on and start killing 2 of your units per turn each.

It does, but (except Hammer & Anvil). But Venoms and Ravagers like to do so anyway. Idea is shoot his gound AT (Oblits, Havocks) before it does yours.

DE should be fast enough to get to the midfield/opponents side even if starting late as T3

Obviously this tactic doesn't work great with assault lists.

Would Vengence weapons batteries work?