yep, wave serpents just utterly destroy FMC's. I'd be surprised if a flyrant lived past turn one.
ray - you can't outflank anything that can hurt a serpent in the nid dex. Nothing with the ability (or that can be granted it through hive commander) has a gun that can hurt it.
The sheer amount of high AV that guard can field can certainly give wave serpents pause, so I'm interested if that shakes up the meta.
I've found with playing nids vs. Eldar, a couple serpents is manageable if you can be very aggressive... three is getting pretty dicey... anymore and you just don't have the ability to shift it. Problem is that the things that can reliably hurt a wave serpent with nids are extremely rare.
- Forget close combat, no decent Eldar player is going to let an MC get that close (you could outflank a tervigon with hive commander, but then it sits there for a turn not attacking and either gets shot off the board or the serpents just move away)
- flyrants in rear arc? He has to let you fly behind him... so two turns minimum. With 7 serpents that flyrant isn't crossing the board... even two.
- a decent sized unit of dakkafexes with onslaught on them can usually take one out first turn... but that is a crapton of points to deal with a 140 point transport (3x as much!) and if it's got holofields, cover and maybe moved... yeah gets even more dicey at that point... and that's ONE.
- crone vector strikes can stop one fairly reliably (no cover and all) but if he isn't shooting your FMC's with his serpents (heck two per FMC should be easily sufficient to kill them all in one turn) you're smiling. They won't let you smile... it's right there in the dex under wave serpents pg. 23 "other player not allowed to smile or have fun"
- Hive guard can wreck them. So this may give the Eldar player something else to shoot at first turn. again onslaught is mandatory due to the limited range.
An alternative to what you're running and pretty much as anti-eldar as you can get would be a less initially aggressive list that I call the brick. The key is that with 4 rolls on the table you hopefully will get catalyst. The prime joins the venomthropes to soak wounds (why he's not the warlord!) and if you get catalyst ONCE the venomthropes/prime are the target... with a 3+/FNP and shrouded you should be able to last the 2 turns needed to cross and in combat he's no slouch. If he ignores the tyrannofexes you will wreck him. If he focuses on them he won't get them all by the time you get close enough to engage so long as you can keep them alive (after turn 1 the t-fexes can become the target for catalyst, especially if you get it twice as one should die)
HQ:
Deathleaper - hiding out of LOS - extremely easy to do due to the wall of death before him (stealth + shrouding from thropes and can only snap fire against him? pretty decent)
Tyranid prime - maw claws of thyrax - he's a wound soaker for the thropes and decent if he actually hits combat.
Troops: gaunts are bubble wrap... that's it... they run in front of the t-fexes as a screen... when numbers get low make more, place all your objective right in the middle or in your opponent's deployment zone. That's where you're going. Tervigons run behind the t-fexes flanking the thropes
Tervigon
Tervigon
30 termagants
30 termagants
Elite:
3 zoanthropes
3 zoanthropes
2 venomthropes
Heavy: The front of the brick... with a 2+ save and shrouded even Eldar will have a hard time removing them. Wave serpents don't ignore any AP and with that list he's NOT getting out of them unless he has to. s6 AP4 torrent templates are like having three helldrakes VS eldar.
Tyrannofex
Tyrannofex
Tyrannofex
1850 (since that's the level you play at)
everything moves forward as a unit... deploy like this:
xxxxxxxxtermagantsxxxxxxxxxx xxxxxxxxtermagantsxxxxxxxxx
tyrannofex tyrannofex tyrannofex
Tervigon zoans venoms/prime zoans tervigon
deathleaper (good luck drawing LOS to him through all that!)
now you may be asking yourself, how you kill the wave serpents at range? You don't. I know what you're thinking "that's stupid!". Yeah well you're not killing the serpents before you get there. Life is sad like that, you weren't going to anyways and losing 3/4 of your army trying to kill 3 of them doesn't work. But given the right powers he's also not killing you in the two turns he needs to. When you're close enough (20") start lobbing templates, even if they do absolutely nothing. Draw attention to the big nasties up front, even for just a turn. warp lance a serpent and then template the living shit out of anything inside. Yeah it's one serpent... rinse and repeat. Two down and now you're close enough for a turn three charge no matter what... charge the serpents, template the contents, bubble wrap the objectives with a sea of gaunts... dare those jetbikes to come anywhere close to your shadows/ID template brick (if he's got 7 serpents plus contents and two farseers there can't be much else at 1850... I hope)
"But the brick is so slow!" well he isn't scooting around you to the back of the board (he might try, let him because there's no objectives there). If during objective placement he sees what you're doing so puts his there, then brick around them, make bubble wrap and call it a game of no fun for anyone.
I don't know if it would work, but it might last longer at least...just make sure you can rock those 2+ saves!