Wednesday, October 26, 2011

Tyranid Library - the Fexstar

Alright gribbly horde fans, I've been promising a library article on the fexstar for a while now, so here it is.  Even better I hope, Ill get to talk about my learning experience with the fexstar from NOVA.

The classic fexstar, for the uninitiated, is two Tyranid primes plus two carnifexes with quad twin-linked devourers, also known as a 'dakkafexes'.  The main benefit of pairing two primes with a brood of two carnifexes is to take advantage of the "50% or more of the models in a unit" cover rule.  The primes, as ICs, can get cover from ordinary infantry units, and when they attach to the carnifex brood, confer this ability to the unit as they comprise "50% or more" of the models in the unit.  This means the carnifexes are no longer working under the much more vulnerable True Line of Sight (TLOS) cover rules for monstrous creatures (MCs).  The variant is the "mini-fexstar" of one prime and one 'fex; and the same cover principle still applies.  An alternate setup is to use a dakka tyrant and tyrant guard; different rules to get there, but same impact on cover.

As far as biomorphs and weapons go, the 'fex is pretty straightforward.  In my opinion, the only biomorph worth consideration is frag spines to allow an I3 charge into cover to get ahead of thunder hammers and powerfists.  It's definitely possible to build a melee deathstar and keep the dual scytals on the fexes instead of devourers, but this article is focused on the dakka version.  I've seen quite a few prime variants recommended, but the prime is just such a good unit it almost doesn't matter what you give him.  Regen is probably the most common, but I've seen both AG and poison; all have their advantages and depend on your playstyle and preferences.  For weapons I prefer bonesword/lash whip; the I1 effect for models in base contact is just too good defensively as the fexstar definitely can attract opposing assaulters/deathstars; I don't upgrade to a deathspitter, but would strongly consider it for the mini-fexstar variant.

Just to recap, here's the list I took to NOVA:
Prime: BS/LW, Regen
Prime: BS/LW
3x2 HG
2x10 Genestealers w/tox, w/BL (w/scything talons) (11 models per..)
Tervigon w/TS, AG, catalyst, onslaught
Tervigon w/TS, AG, catalyst
2x 10 termagants
1x2 carnifex brood w/2x TL Devs, frag spines
1x3 biovore brood

So let's put this into the context of the NOVA scenarios and why I ultimately went with a fexstar as my core: win conditions alternate between objectives, kill points, and table quarters.  I decided to give myself as much of an advantage in two of the three as I could:  Tyranids are generally pretty decent at objective missions being an assault-oriented codex, plus the ability to park T6 MCs on objectives as troops.  Unfortunately, tervigons are also kill-point generators, and with no shortage of units that can be relatively easily taken off the table, kill points missions can be a challenge.  Table quarter missions however, are all about having more points in a quarter than the other guy: an expensive, tough unit that can torrent or assault effectively, and is best suited for the center of the board where you can pick and choose a table quarter when needed is just the ticket.  Weighing in at just under 600 points, the fexstar can and did win me table quarter battles.  I also took into heavy consideration Mike's blog article describing the tall, x-deployed terrain, and with the expected cover advantage and lanes of fire, I had a reasonable expectation of this unit both not being blown up immediately - especially with conventional wisdom placing target priority on the hive guard and tervigons - and being able to torrent down both hordes and expensive, small units like Thunderwolves and Grey Knights.

I did mention torrent there, and most of my opponents were shocked at just how much fire the fexstar throws out.  24 twin-linked shots averages out to around 18 hits; at strength 6, they're wounding on 2s and 3s against just about anything else.  Add in another 6 shots at S4 with BS5 from the primes and you can pretty easily force ~15-20 wound saves on whatever you shoot at; and instant death on T3s.  One or two shots from this unit can flat out erase most infantry units unless very large or very resilient.  Even when split into the single 'fex variant, you're still looking at 15 shots, 10ish hits and ~8 wound save rolls.  More than a few folks prefer the flexibility of two units, and frankly I like the idea too - just not for a NOVA-style event.  Another key point was most people forget termagants can shoot, and if they're along for cover, you're probably going to be able to throw a few S4 AP5 shots into the mix due to the range.  An 18~24" threat range (counting move) with that kind of firepower is a pretty big deterrent.

A critical rule to remember is the AP "-" so it gets a minus on the vehicle damage chart, but if you're throwing that many shots at a vehicle you can penetrate with S6, it is extremely likely to take multiple penetrating hits.  One very important thing to remember with AP-, vs. non-open topped vehicles, it is impossible to get an 'explodes' result.

While that 18~24" threat range sounds great, keep in mind the big boys take up real estate.  If you're bringing your own cover in the form of termagants, that are also in cover - requiring a move through cover roll - your fexstar can get hung up in terrain and traffic pretty easily, making that 18" range more like 19-22.  This needs to be a constant consideration for your next-round planning when fielding a fexstar.

Things I forgot consistently at NOVA: wound allocation and attempt to regen.  For victory point battles especially, a damaged prime is half again less than a damaged fex; depending on gear, even a dead prime can be less costly to VPs than a damaged 'fex.  I also forgot to roll the bonesword chance for instant death on unsaved wounds.  Whatta newb!

Things to watch out for: Probably obvious to most, but for newer players, anything with AV13 can wreck a fexstar's day unless you can get the 'fex into assault with it, and even then, absent the dual scything talons, you may have a rough time.  Thanks to Sean Nayden for that painful lesson ;)

At any rate, I'm definitely not an authority; the above simply reflects my learning experience and opinions.  As promised, Here are some additional articles on the dakkafex and/or fexstar.

Probably the best article I've seen, plus OST is always a good read:
He also has a nifty article that discusses using the dakkatyrant as a replacement for the dakkafex:

Abusepuppy remains one of my very favorite 'nid muses; I love the 1k list here:

A solid discussion by Purgatus on the fexstar's synergy with other units, biomorphs, and point efficiencies:

No library article on the fexstar would be complete without Hulksmash's influence.  He has multiple articles and batreps on the fexstar that I drew on heavily when building my list for NOVA:

Hope you enjoyed it; please feel free to add links to other articles on the fexstar or dakkafex you think should be here in the comments!


  1. "48 twin-linked shots averages out to around 36 hits; at strength 6, they're wounding on 2s and 3s against just about anything else. Add in another 6 shots at S4 with BS5 and you can pretty easily force ~30 wound saves on whatever you shoot at; and instant death on T3s. One or two shots from this unit can flat out erase most infantry units unless very large or very resilient. Even when split into the single 'fex variant, you're still looking at 29 shots, but closer to 20 hits and 10 wound save rolls."

    Um, what? A pair of Twin-Linked Brainworm Devourers are going to give you 12 shots. Two pairs will be 24 shots. Where are the 6 S4 BS5 shots coming from?

  2. Fixed! Accidentally used the stat line for 2 broods of 2 in my notes. What I get for posting at midnight.

  3. Thank you very much for the shout out and I am glad you enjoyed the article. Do try the tyrant version, it is really quite game changing to have the paroxysm available and also takes some heat off the Tervigons. You also have your heavy spots open in larger games, making it possible to spam biovores in small hiding units OR if you're a big spender, the T-fex, though I think that may be another list altogether.

    In any case, the fire-power is very nice and if you have problems with DE, you can say "I used to have problems with DE" after fielding the unit!