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Devilfex- 2x Twin-linked Devourers, Enhanced Senses
Ninjafex- 2x Scything Talons, Adrenal Glands (WS), Toxic Miasma, Flesh Hooks
Boomfex- Barbed Strangler, Scything Talons, Flesh Hooks
None of those! I have a different build I like to use! (please post below)
I was just wondering, because in the 1500 pt list I am building up to I used to have 2 ninjafex's in my elites slots. Now I have decided to go with some Boomfex's instead, those extra strength 8 pieplates just seem to good to pass up.
I was thinking about some devilfex's, but both my tyrants are running devourers so I thought they had that covered.
What sort of elite 'fex does everyone else like?
"I am the architect of fate!"
I voted for the Boomfex (so needs a new name). I think it looks fun and I want to make some out of old 2nd edition Carnifexes I used in back in ye old days of yore, the 90's. I have three lying about somewhere and being generally useless and in need of repainting. Though I will have to find some barbed stranglers to use on them, don't know if I have enough spare ones.
However I was thinking I might remove a pair of scything talons on one. They could be replaced by spinebanks and rending claws. This would be done to get the spinebanks, the rending claws are useless on a Carnifex but it must have two weapon symbiotes and rending claws is the cheapest and also the only one it can afford and stay in elites. The spinebanks could be used to add some extra firepower and against lightly armoured infantry or light vehicles may be handy. The loss of the sything talons may not be a huge prolem as they don't add a huge amount and one Carnifex with extra shootyness would add some variety.
i voted devil/dakka fex purely because its the only 'elite' carnifex i have used. and it has worked well. but honestly i don't think they look so hot with their little devourers. i think the boom fex or ninja fex looks so so much better, but then when i think about those eight s6 shots that re-roll to hit and wound then i don't mind it so much its kinda a trade off for me - its looks for its effectiveness. that probably applies to everyone.
this is my order of preference - 1 dakka, 2 boom, 3 ninja/screamer. mine is a ranged based swarm anyway.
i just see a ninja/screamer fex looking so much meaner and would instantly draw 4 krak missiles and die before it would ever get close enough. poor thing!
I went with the boomfex myself. I also plan on running a shooting oriented army and my Tyrants have the whole 2x TL Devourer thing handled (Lets throw more rerolling dice at them then they can handle!)
Because of this I went with the boomfex. Between my Elite Boomfex's and my Heavy Gunfex's I hope to have enough strength 8 pie plates to make my opponent crap his pants.
"I am the architect of fate!"
Well, I voted Devilfex (aka Dakkafex) for sheer mid range killy power, but there is a pretty sneaky trick if you have Boomfexes. Get a group of three Zoans and two Tyrants all with psychic scream. That is a -5 to every one's leadership that is in range of all of them. Get a big group of Boomfexes and start throwing blasts. Soon the enemy's army will be taking (and loosing) -5 pinning tests left and right, allowing the rest of your army to get into place, assault, and fire on them without fear of getting mowed down on the way! Now, you have to get all those brain bugs in range, and the point cost is pretty darn high, but it is a pretty wicked combo.
Thats a sneaky trick. I think for my elite fex, I'll probably be using a boomfex.
Ah boomfex--Not really worth it. Without Enhanced Senses you won't be hitting much with one shot per round.
"What is Mercy? Does it taste Nice?" Hive Tyrant on Reth V
"Kill-kill! Death to the Enemies of the Horned Rat!" Warlord Bweekq at the Battle of Hrad
The boomfex didn't really work for be, because I seem to keep blasting my own models to pieces too! Just so humillliating...
The Ninjafex has the best looks and you can really use that scaryness to mess with your opponents. But still, the dakkafex performs better!
Tyranids Win / Draw /Lost 
Daemon Hunters Win / Draw / Lost 
I use 2x ST, bio-plasma, AG-WS.
Bio-plasma is for skimmers and just the general extra attack. I run two of these to give mobile cover to my walking dakka tyrant and to eat wounds. Either people have to dedicate anti-tank shots to the CC fexes or let the fexes hit their line. They generally don't make back their points directly, but my HTs generally don't get shot at till later in the game because of them.
"The internet perceives censorship as damage, and routes around it."
Okay, it looks like the dakkafex is winning, and I have to admit that I voted that way. But, here is the question, in a nidzilla army, what would your second elite fex be? Another dakka or a Piefex? I currently carry on dakka and two pie in my elite slots, but is this the best load?