Sacrifice…..
is quite the unique power as it summons a herald at the low cost of 1 warp charge and a wound off a nearby unit (good bye free Pink Horrors). Being that you’re only getting a single 2W model that can’t use its Independent Character rule until after your opponent took an entire turn you aren’t summoning heralds to contribute to your board presence as they will die to a stiff breeze. Instead you summon heralds for the utility their 30 point buying allotment grants them. All heralds can buy a Hellforged Artifact such as the Portalglyph or Grimoire of True Names if you didn’t already have them (though the herald will have to survive for an entire enemy turn to actually get to use them) and by placing another daemon character on the board you reduce the chance of an actual important daemon character (like Fateweaver) being randomly picked to explode to the ‘3’ result of the Warp Storm. But each god’s herald does have some nifty perks they specifically get that you might find useful in a pinch.
Herald of Tzeentch – Probably the best of the four choices simply for coming out as a Level 1 Psyker standard before you even buy one its many amazing options. You could simply buy Master Level 2 and boost your ensuing psychic phases. Or put your herald on a disc to gain sweet Jet bike status for a low warp charge cost objective grabber (or easily get out of LoS to survive for more than a turn). You also have access to two excellent Tzeentch artifacts; The Impossible Robes and Paradox. Paradox is an awesome relic both lets you guarantee cast one psychic power each turn and save on warp charges at the same time (really you should already have this in your Chaos Daemon lists). The Impossible Robes 3++ invulnerable save gives your herald a strong chance of just shrugging of any damage allowing it to actually try and hold an objective on its own (especially if you turn it into 2++ rerollable with Cursed Earth or the Warp Storm). Herald of Tzeentch’s variety of upgrade options really makes it the little swiss army knife of summoning.
Herald of Slaanesh – Probably the only other Herald worth buying a psyker level for due to its access to Telepathy allowing you to take a swing at rolling Invisibilty or Shrouded or at the very least take Psychic Shriek and try to blow up a unit (which just like Flamers, turns your Sacrifice power into a nuke spell). Unfortunately no great artifacts to summon for since they all require making it to close combat to utilize but the Herald of Slaanesh can actually buy a Seeker Chariot to ride in on utilizing its 15” flat out movement (thanks to Daemon of Slaanesh) to grab an objective while effectively being an 11/11/10 Land Speeder with a Daemon save make her immune to small arms fire while not actually being weaker to heavy weaponry since it would just Instant Death her anyway, if anything she is more survivable against heavy weapons since they don’t wound on 2+ anymore. These are solid options for a WC1 power.
Herald of Nurgle – There are several options for your Herald of Nurgle. You can take the Greater Locus of Fecundity for FNP to attempt for a cheap WC1 objective camper or try to give FNP to one of your Nurgle units (if you can make it to them). You could take Psyker Level 1 and fish for a blessing like Endurance or Putrescent Vitality to buff a friendly unit. You could also take Death’s Head of Duke Olaks for a single shot large blast that’s 2+ poison AP4 to try and blow up a unit (pretty funny to pull that little trick out). Or you can do the best option for the Herald of Nurgle is by the Doomsday Bell to give your entire opponent’s army -1 LD. That’s pretty strong against armies that susceptible to morale and pinning checks but even against fearless armies you can combo it with Psychic Shriek and the like to deal more damage. Some neat little tricks to surprise your opponent with.
Herald of Khorne – Not really a lot of options here folks. Can’t afford its mounts, can’t take a psyker level, and its entirety of relic options are melee weapons for close combats that the Herald probably will never reach. Your best choice is to buy a melee weapon or locus (either Adamantium Will, Hatred, or Rage) and try to add it to a Khorne unit in the following turn.
Bonus Tactic! Boon of Flame
While not a Malefic discipline power it is worth talking about because Chaos Daemons armies have easy access to it thanks to Fateweaver and the Endless Grimoire artefact since both let you know the entire Change disciple automatically. This lets you summon Flamers (already discussed) but also an Exalted Flamer or a Burning Chariot which is quite unique.
Exalted Flamer – The Exalted Flamer is a neat independent character with a massive drawback. It powerful guns (D3 lascannon shots or a torrent S5 AP3 flamer) but the problem is both are 18” ranged Heavy weapons and the Exalted Flamer is not relentless. While it only cost 2 warp charges to summon it this drawback is too great for effective utilization because you can’t fire on the turn you summon it and it just is too easy to move out of its range of its guns when it remains stationary. Short of building an army around using Exalted Flamers the only real use is to summon one join a unit of Pink Horrors so that they have some counter fire and something to overwatch with which just isn’t worth it.
Burning Chariot – This is what you want because this is the Exalted Flamer without its massive drawback. Being a chariot means you benefit from Relentless so can move and shoot either of its Exalted Flamer’s excellent heavy weapons. This is especially potent since it has such a range of threatening damage you can attack any unit you want and have a solid change of hurting it (vehicles, MCs, hordes, your name it). It’s also a fast skimmer too so have great mobility with even a 18” flat out move. Unfortunately it’s very fragile being only Av10 with 3 wounds and hull points it isn’t hard to shoot down. But it has enough kick to be useful for the one turn you get to use it for either for hitting a unit hard or for grabbing an objective for the turn.