This is perhaps my favourite unit on the tabletop, or at least one of them. These are Battle Sisters with +1 Weapon Skill, a jump pack and two bolt pistols instead of the usual boltgun. Their Act of Faith gives all of their weapons the Shred special rule for a single Shooting phase which works wonders with the option of dual hand flamers. The dual hand flamers is the only real build for this squad as the inferno pistols are insanely expensive, especially considering the hand flamers, the weapons that were generally taken, have decreased in points cost. Inferno pistols are a nice idea, but for a horrible number of points you get two meltas with half the range, which means that you have to be within 3″ to get the +2d6 armour penetration. Paired with the fact that the Act of Faith does not synergise well with tank hunting, it is far better to outfit Seraphim with as many dual hand flamers as possible (so… 2). With Weapon Skill 4, they may just have the punch to deal with the tattered remains of whatever they wrecked in the Shooting phase by charging in the Assault phase. This is aided greatly by giving the Seraphim Superior a power weapon of some description, it does not really matter which though I prefer the standard power sword, and a plasma pistol can help though is not as important; the squad also has access to the Hit and Run special rule, allowing them to charge in, fight until the next Assault phase and then break off ready for your next turn of shooting, shielding them from any shooting your enemy would have directed at them. However, remember that they are only Inititative 3, Strength 3 and Toughness 3. The only real drawback of this squad is that they cannot take a Simulacrum Imperialis, so they are only able to gain the Shred special rule for one shooting phase.. They also have the ability to re-roll their Shield of Faith invulnerable saves, which is nice but not game changing. I will always take a unit of Seraphim because as I said, they are the best looking unit in the entire game.
Dominion squads are decent at hunting down tanks with lots of melta guns and turning them into slag. Dominions are equivalent in statistics and special rules to Battle Sister squads, apart from costing +1 point and having the Scouts special rule. Their options are also the same, apart from being able to take no heavy weapons, instead being able to take up to four special weapons, and up to five additional Dominions; they may also take the same Dedicated Transport options. Their Act of Faith is definitely worth getting a Simulacrum Imperialis for, allowing them to use it twice. For one Shooting phase all of their weapons gain the Ignores Cover special rule, meaning that your melta guns suddenly ignore whatever kind of shelter your opponent has used to keep his vehicles alive. I play Eldar and rely on my 3+ cover saves afforded by Jink and holo-fields, my Imperial Guard vehicles all use camo-netting, even my strategy for my Sisters’ tanks is to keep them largely in cover; an Act of Faith that lets you ignore cover saves means that you could very easily wreck any tank within 6″. I do not believe that the flamers or storm bolters are worth the points, as Battle Sister squads can fulfill the anti-infantry roles alongside Retributors, though Retributors will be covered on the Heavy Support page, storm bolters are generally a bad choice as a special weapon for your squad and flamers ignore cover anyway.