Editing Warhammer 40,000/5th Edition Tactics/Tyranids (section)

==Building Your Army==
The central power of Tyranids this edition is in swarms of units. Among the best performers for the army are Hormagaunts and the swarm-producing Tervigon, but Termagants armed with Devourers (termed Devilgaunts by many in the community) aren't half bad either with a bit of cover. Thanks to Warriors being troops, it is possible to build an army with an elite focus as well, but the Tyranids don't take to such list building strategies as well as certain other armies do. This is mainly because hidden powerfists will put an end to Warriors in an eyeblink, preventing them from making safe assaults into any Space Marine unit toting one.

Unfortunately, armies with a great deal of attention to monstrous creatures will often find themselves fragile and horrifically outnumbered. A bit of number crunching reveals that, per point spent, a carnifex is not all that much more durable than a bunch of hormagaunts in cover, meaning that small arms are no less effective against them and heavy weapons are an unnecessary Achilles heel. Some of the newer monstrous creatures with six wounds, such as the Trygon, keep it together better but just can't do everything the army needs thanks to their high cost and few numbers.

*'''General List Building''' - For the most part, Tyranids have very few options to choose from once they have selected the models they wish to use. For example, Hormagaunts have only two biomorph options: adrenal glands and toxin sacs, and the same is more or less the case for Termagants, Gargoyles, Trygons, Mawlocs, and several others (plus or minus one or two biomorphs). The strong point of the army is not in mutable units or myriad alterable roles this edition. Hence, the following is a list of the three most common biomorphs and their most prominent uses:
**'''Adrenal Glands''' - This biomorph grants Furious Charge to the model it is equipped to. Its foremost use is increasing strength to better damage vehicles, but it also proves helpful for getting the first strike in melees; while marginally less useful against infantry than Toxin Sacs, when the two are used alongside each other, basic Tyranid infantry become among the deadliest anti-infantry in the game (for a price, that is: it is often better to choose one biomorph or the other).
**'''Toxin Sacs''' - Toxin Sacs cause the model's close combat attacks to be inflicted with a 4+ Poison, which is quite potent against enemy infantry and monstrous creatures. Although they are offered to all Tyranid monstrous creatures at needless cost, they will most typically hinder the efficiency of the big creatures since wounding on a 2+ (83%) is better than wounding on a re-rolled 4+ (75%). However, they have the tendency to be very useful on infantry units, such as Hormagaunts, and when taken on a Tervigon the 4+ poison bonus is granted to all Termagants within 6" of the beast.
**'''Regeneration''' - Typically expensive, this biomorph allows a model to roll one die for each wound it has currently sustained. On each roll of 6, a wound is recovered up to the model's maximum. Though available to Carnifexes, Hive Tyrants, and Harpies, it is a choice that is most useful to six-wound models like Trygons or Tervigons. When placed on a Tyrannofex, the model becomes pointless to shoot at; after all the work it takes to wound one, it's completely demoralizing to watch it just recover the damage. However, it is usually quite costly to be putting on any model without crucial importance to the army as a whole. It is rather cheap on Tyranid Primes, though, and not so bad on Harpies, either.

*'''Harpies''' - Harpies are flying Monstrous Creatures. At first glance, they're expensive and fragile since Strength 10 weapons can instant-kill them, and they only have a 4+ save. To make the Harpy worth the investment, a Tyranid player must provide it with cover and provide enough immediate threats to make targeting the Harpy itself a less demanding proposition. 
**'''Role:''' The Harpy shoots, providing ranged support to the Tyranid army. Armed with its choice of Stinger Salvo or Cluster Spines and Stranglethorn Cannon or Heavy Venom Cannon, it can be tailored against infantry or modest tank suppression, typically preventing enemy armor from firing by scoring stunned and shaken results. Although they are not geared for close-combat, Harpies can provide secondary melee support if desired on account of being one of the few Tyranid models with Assault Grenades and on account of their special rule which halves the initiative of enemy units they charge. Although this secondary role is more situational (Tyranid models as a rule have some of the highest initiative-values in the game), against similarly high-initiative enemies like Eldar Harlequins, the results can be meaningful if properly pulled off.
**'''Purchasing Harpies:''' At lower-point levels, the Harpy isn't needed since the Elite anti-tank options are generally sufficient for dealing with enemy armor; at higher point-levels, more durable anti-tank firepower can be had in the Heavy Support slots. What Harpies do is allow Tyranids a degree of flexibility, allowing them to more freely choose alternative slots in the Heavy Support or Elite slots.

*'''Hive Guard and Zoanthropes''' - The two foremost solutions to armored vehicles in the Tyranid codex, these models must appear in every Tyranid list that expects to encounter tanks or armored transports - and let's face it, tanks and armored transports are in almost every serious army list out there in 5th edition. One is better for busting transports while the other handles heavy armor as if it were blasting retarded, wingless goslings with a twelve gauge shotgun; one shooting phase, one kill tends to be the normal for a full unit of either model. Hive Guard and Zoanthropes are completely in their own league as far as anti-armor power is concerned, outclassing everything else in the codex by embarrassing miles. Zoanthropes do have some trouble dealing with Psychic Hoods, but that aside, it is usually wise to figure how many points are going to be spent on Hive Guard and Zoanthropes before adding any more units to the list.

*'''Tervigons and Termagants''' - The two models really must be addressed together when list building because one is as good as useless without the other in most cases. The Tervigon, which spawns 3D6 Termagants at the beginning of each phase until it rolls doubles, provides buffs to all gaunts within 6" of it. The buffs include Furious Charge and poison if adrenal glands and toxin sacs are equipped to the Tervigon respectively, and all gaunts within 6" of the Tervigon always have Counter-attack. The only drawback is that, should the Tervigon die, nearby gaunts can take damage, but thanks to six wounds, a toughness of six, and a relatively non-threatening profile, Tervigons don't go down all that commonly. Tervigons can also purchase a psychic ability to give an entire unit Feel No Pain, so in short summation, one Tervigon turns a unit of sniveling, weakling Termagants into a unit of half-decent combatants. Furthermore, whenever Termagants are purchased, a Tervigon can be included as a Troops selection, so there's honestly very little reason to ever take one without the other.
**'''Role:''' Both models are Troops first, meaning they are best used to jealously hold objectives. A Tervigon can often be difficult to shake from a position it takes up, especially if it can find cover somehow, and as long as the Tervigon can continue to pump Termagants out onto the battlefield, there's never a shortage of bodies to claim ground. Unfortunately, neither unit boasts much overt power in general. Tervigons have a shooting attack, but it's mild due to modest ballistic skill, and the same is true of Termagants. Also, despite potential boosts from Furious Charge, poison, and Counter-attack, Termagants are still not really all that great at fighting. They can lash out opportunistically, but the buffs merely make them worth the effort, and returns diminish sharply in turns following a charge.
**'''Equipping Gaunts:''' Gaunts may have numerous potential weapons, but only two are worthy of consideration: fleshborers and devourers. Spinefists, the third mainstay in the cold, are not more efficient at shooting than fleshborers, and because they are more expensive they are not to be minded for any reason. One in every ten Termagants can also take a S2 flamer that attacks enemy strength rather than toughness, but the cost of the gun is twice the base worth of a Termagant, so no luck there. Then there are also spike rifles, which are just spinefists with longer range, no AP, no twin-linking, and the same cost. In contrast, devourers boast Assault 3, S4, and a leadership lowering special rule, all of which can be very potent at an expense of high fragility per point to the equipped models. Lastly, fleshborers are a cheap option that keeps Termagants expendable while still allowing them to pack a bit of punch against the rear armor of transports.

*'''Trygons'''
**'''Role:''' (The following calculations assume the purchase of Adrenal Glands; an upgrade which is highly recommended) It slices, dices, and fries small infantry units, and a majority of vehicles. Even against enemy vehicles attaining Cruising Speed, the Trygon's weight of attacks and Scything Talons provides an almost 50-50 chance of killing any rear-AV 10 vehicle (the vast majority of vehicles in 40k); these odds correspondingly increase against slower vehicles. Be it for a Tyranid Reserve army, or a horde, the Trygon acts as a linebreaker for the rest of the army.
**'''Drawbacks:''' In most games, it will be impossible to find cover for the Trygon on account of its height. Compounded with its lack of an Invulnerable save and huge threat potential, it will be a high-priority target; a single Trygon emerging unsupported will die. The rules for Trygon Tunnels are near-worthless: Reserve-based armies generally wish to arrive at once rather than simply running into the slaughter piecemeal, and most Tyranid infantry units can purchase Mycetic spores for marginal costs. An useful, yet expensive tactic for the use of Trygon Tunnel is playing a deep-striking Trygon with an unit of 20-30 Termagant with Devourer to shoot 60-90 S4 shots to enemy infantry, thought there could be several problems with it (for example, Termagant coming in play before the Trygon). Finally, the Trygon itself is not ideal for taking on heavy transports like Land Raiders, both on account of unreliability (the odds of destroying or immobilizing a cruising Land Raider are about 30%) and on account of such vehicles often carrying the very units designed to destroy big monsters. This means that the Trygon works better with armies using Zoanthroapes as their primary anti-tank. As with other Tyranid Monstrous Creatures, the Trygon must be screened against assassin-type units, primary examples including Genestealer teams or the Librarian Furioso.
**'''Upgrades:''' Adrenal Glands are a good choice for the Trygon. Being Fleet allows the Trygon more opportunity to fully take advantage of Furious Charge, the extra Initiative allows it to strike before Marines (and more importantly, their Dreadnoughts), and the extra point of Strength makes it more adept at taking out enemy vehicles. For the cost of two Termagants, it's a steal. For a fair increase in points, one can optionally upgrade the Trygon to a Prime. Aside from buffing its Leadership (useful mostly for surviving against enemy Boneswords/Neural Shredders/similar threats), and upping the range and output of its Bio-electric Pulse to something slightly more formidable (though still not preferable for use compared to an assault), it most importantly makes the Trygon count as a Synapse Creature. Depending on the build involved, having a Prime Deep Strike can make it a good "relay point" for armies relying on rapidly advancing into the enemy lines, or a way to deliver Shadow of the Warp into the enemy lines. Regeneration is alright due to the Trygon's high wound count, but not necessary. Toxin sacs should always be avoided since 4+ poison is statistically less powerful against nearly anything the Trygon might be fighting, barring other monstrous creatures.