Valkyrie's Guide to Dealing with Titans.
This guide is designed to show the best and worst methods of dealing with Titans of various races. This covers various ways to destroy hostile God Machines with both ranged and assault weapons.
Before analysing each Titan, there are a few concepts that should be considered when engaging hostile Super-Heavies.
Even if you're playing against the smallest type of Titan, the Warhound, getting it into adequate cover can be very difficult. A Forge World Warhound requires about a 4 story building or ruin to provide enough cover, Reavers and Warlords requiring even more. Tracing LoS to a Titan is very easy, meaning that precise troop placement is less important when up against a Titan.
However, cover also is important for your troops too. Many, but not all Titan weapons ignore cover, meaning that you should hunker down behind a ruin where you'll get a better chance of surviving than without cover.
2: Expendable units
In Apocalypse, it's always worth taking a cheap, expendable unit or two to protect your dedicated tank-hunters. The most obvious choice is Conscripts for Imperials, but any unit that you don't mind getting obliterated will serve fine. These units act as a mobile 4+ cover save and speed-bump for your forces.
Some expendable units may even do some damage to the Titan, therefore it's worth taking any anti-tank option for the squad if you have the points spare, such as a Melta-Bomb for a Sergeant. I've seen such an occation where a plucky Comissar took 2 Structure Points off a Warhound by a lucky Chain-Reaction roll. Melta-Bombs, EMP Grenades and Demo-Charges are all useful for this purpose.
Load up on Melta. Weapons that roll 2D6 for penetration are the bane of any Super-Heavy. Squads that can take more than one Melta weapons should be designated as one of your dedicated tank-hunters. Imperial Guard Veterans and Chaos Havocs / Chosen spring to mind, although getting them within the valuable half-range may be difficult.
4: Void Shields
Use semi-powerful weapons, such as Auto-Cannons or Bright Lances to wear down Void Shields. Each Void regenerates on a 5+ for every Structure Point the Titan has left, which means that sustained fire will soon wear down all the shields.
If you have a spare Strategic Asset, you may want to consider a Vortex Grenade. VG's are a bit of a hit-or-miss tactic, as it will either perform brilliantly, or blow up in your face. Giving the VG to a Deep-Striker will allow you to plant it without the fear of being shot up before you get within the 6" range. The large area that a Titan takes up will mean that even when the Vortex scatters, it will most likely scatter back onto the Titan, causing more damage to it.
However, Vortex Grenades only have a 6" range: If it dosen't hit the Titan it has a chance of scattering back onto the user. Give the VG to a squad that you wouldn't mind losing, even Chaos Terminators would be fine for this role. Also, do not solely rely on the Vortex to take the Titan out, as the Vortex can only remove 3 Structure Points at a time. While this gives you a 1/3 chance to destroy an undamaged Warhound, if you're facing a Reaver or even a Warlord, you will need extra support in order to finish it off.
Now we've covered the basic concepts of Titan-hunting, let's have a look at each race and how they can deal with God-Machines. I have deliberately left Dark Eldar off this list as I have very little knowledge of their weaponry and tactics.
The Imperium has some of the best anti-Titan squads available. The most obvious choice is a squad of Veterans with 3 Meltaguns, the Demolitions doctrine and flying in a Vendetta. The Vendetta can Deep-Strike behind the Titan within the Voids, allowing the Vets to open fire at the vulnerable rear armour once they disembark next turn, and then assault using Melta Bombs from the Demolitions doctrine. Using Stormtroopers allows them to strike quicker (as disembarking if the Vendetta moves Flat Out), but they're effectiveness is reduced as they can only take 2 Meltaguns.
Other good choices include Heavy Weapon Teams armed with Las-Cannons parked in heavy cover. Using the Bring It Down! order can seriously increase their power, allowing them to re-roll hits against the target. HWTs with Auto-Cannons and Missile Launchers are good at taking down Voids.
Terminus Ultra Land Raiders can cause serious damage. 5 Las-Cannons, 3 of which are Twin-Linked is almost guaranteed to take at least a few weapons offline for a while. Even though the Terminus has a very small chance of damaging itself when firing, the advantages greatly outweigh the disadvantages.
If you have 450 points and £60 spare, it's worth getting a Shadowsword. You get a Destroyer 5" blast 120" range weapon protected by AV14 and 3 Structure Points. Adding the extra sponsons for +100 points is a good option, as two extra Las-cannons which means two possible extra Voids taken down or Structure Points lost.
Chaos Havocs are essentially Devestators, but much more expensive. 4 Las-cannons alone are 140 points, without the cost of the Marines. For about 140 points, you can take a squad of 5 Chosen with 5 Meltaguns. They have the Infiltrate ability, meaning that they can get close and strike fast and hard straight away from the start of the game. Giving them the Mark of Tzeench or Nurgle further increases their survivalbility.
Chaos Vindictators can also pack a punch. They have very tough armour, and the S10 Demolisher cannon penetrates Av14 on a 5+, so a Line-breaker Squadron can punch through ruins, then attack the Titan within the Voids with 5" S10 Ap2 Blasts.
Chaos Terminators also work against Titans. Take multiple squads of 3 'Termies', all with Chain-fists: Deep-Strike close to the Titan and assault it during the next turn, each 'Termie' giving 3 attacks with 2D6 penetration, 4 attacks with the Mark of Khorne. Giving them an Auto-Cannon can also provide anti-Void support.
Orks are one of the few armies which I don't collect, although I can make a suitable tactica from what I already know. Lootas are a good choice for wearing down Voids, as a maximum of 30 S7 shots, even at BS2, are bound to strip Voids quickly. However, they cannot even scratch the paint of most Titan's front armour, so unless you have a clear shot at the side or rear armour, leave the hunting to Tank Busters, or even Mega-Nobz: Power Klaws or other high strength CC weapon can tear through Titans, due their low WS, and the Mega Armour provides a 2+/5++, greatly increasing their survivability. Personally, I've seen Wazdakka tear apart an undamaged Warhound in CC, before it was finished off by a Particle Whip.
In short: Power Klaws, Mega-Nobs, Tankbusters.
You can't go wrong with Bright Lances: allowing you to count the Titan as AV12 is a golden ticket when fighting Super-Heavies. Wraithlords with Bright-Lances can harm Titans, both at range and in CC. Taking Fire Dragons is also a must: Using a Wave Serpent, zoom over to the rear armour and unload S6 Ap1 with 2D6 Penetration. If they survive until the next turn they can even assault with their Melta-Bombs. Therefore Fire Dragons are a must them fighting Titans.
Railguns coupled with Markerlights and Target Locks are able to provide very accurate, hard-hitting firepower. Pathfinders each have a Markerlight, and are able to take EMP Grenades. Infiltrate them close to the Titans, and use their Markerlights to designate targets for awaiting Hammerheads and XV88 Teams. Next turn, assault, using their EMP Grenades, with a 1/3 chance of a Glancing or 1/6 chance of a Penetrating hit, these relatively cheap guys can tie up a Titan for a turn while EMP-ing it's ankles. XV8 Teams with dual Fusion Blasters can Deep-Strike within it's Voids, letting loose with 2D6 penetration. A team of 3 XV9s with Fusion Cascades can unleash 18 Melta shots per turn if you're lucky: I would definitely consider a Team of XV9's when against Titans. Broadsides can also provide accurate Railgun fire from 72" range, which can be supported with extra Markerlights.
Tyranids really have no anti-Titan weapons, bar the Zoanthrope's Warp Blast. You cannot rely on this though, as Zoanthropes will die easily to Titan Weapons, despite having a 3++. Hard-hitting Tyranid force relies in their CC abilities, units of Carnifexes are literal ankle-biters, with up to 8 attackers on the charge if they take Crushing Claws. If you take a Carnifex Crusher Brood from IA: Apoc, they can take 2 pairs of Crushing Claws, which following RAW for the formation, gives them +2D6 attacks each, even though Crushing Claws have changed for 5th Edition.
With Necrons clawing at Jervis' office, begging for an update, they have very little to offer for Titan support. Until Jervis steps down from his throne of Dark Eldar skulls, we'll have to deal with Gauss Weapons. With Gauss causing an automatic Glancing hit on a 6 to penetrate, multiple squads of Warriors rapid-firing into the Titan will soon wear it down, and using them in conjunction with a Lord with Resurrection Orb will increase their chance of surviving a volley from Plasma Blastguns, Deff-Kannons and the such. Heavy Destroyers are a good choice too, as S9 fire mounted on a Jetbike allows the Destroyers to flank the rear armour of the Titan and strike it's weakest point.
Any questions or comments? Feel free to contact me - Valkyrie