Looking back at the new Artifacts for Thousand Sons, what really jumps out to me is the Astral Grimoire… being able to make a friendly infantry unit within 12″ into a Jump Infantry automatically (i.e. no psychic or leadership test required) every turn is amazing and adds the critical mobility to so many different units that are otherwise lacking in this area.
As I have looked at it more and more, I think the best candidate for synergizing with the Astral Grimoire is a Battle Group, drawn from a Tzeentch CAD, that looks like this:
-Chaos Lord with MoT, TDA, Chainfist and Lightning Claw, Astral Grimoire Relic
-Exalted Sorceror with MoT, PML(3), Spell Familiar, TDA, Seer’s Bane Relic
-10 Chaos Terminators with MoT, 8 x Combi-Melta, 2 x Reaper AC, 10 x Chainfist
Basically, the idea here is to make a squad that combines the attributes of Assault Terminators, Tactical Terminator, and Jump Infantry, while also throwing in some Psychic powers and Relics to make the battle group even more potent.
First of all, the Exalted Sorcerer rolls hard on the Sinistrum Discipline for Warp Fate ( Diabolic Strength and Death Hex are also solid choices here). If he gets Warp Fate, he casts it on the squad every turn, giving them 2+/3++ saves that can be re-rolled in all phases of the Turn (5++ from TDA, bumped up to a 4++ by MoT, and bumped up again to a 3++ from Blessing of Tzeentch when a Blessing is cast on the unit, with Warp Fate giving everyone re-rolls). Against non AP2/1 attacks, this makes the unit able to shrug off 97% of enemy attacks, on average, and even against those low AP wounds, they still ignore 88% of them with Warp Fate activated. Alternately, you can roll on Biomancy and go for Endurance, which provides very similar effects in terms of overall durability.
If you cannot get Warp Fate, then the Exalted Sorcerer can still use the Force power on his unit, which gives his Daemon Weapon (i.e. Seer’s Bane) Instant Death and also brings everyone in the squad up to a 3++, just like Loyalist Hammernators. On top of this, the entire unit uses the Astral Grimoire to move 12″ every Turn, make them vastly more mobile than most Terminators, and able to get in close rapidly to use their Combi-Meltas, Chainfists, and potent Armor/Invul saves to full effect. The Combi-Meltas and Reaper ACs provide solid high strength shooting against vehicles and tough infantry, while the Bolter portions of the Combi-Meltas and Reaper ACs also give you some “crowd control” options. On top of all this, the Exalted Sorcerer has his “Lord of the Silver Tower” ability, which acts like a poor man’s Orbital Bombardment (i.e. One Use, S9 AP2 Small Blast, Lance).
Finally, when the unit does get into Assault range, it can put out 35 x S8 AP2 Armourbane attacks on the charge, as well as between 7 and 11 AP2 Instant Death attacks from the Seer’s Bane Relic (provided you do not roll a “1” on the Daemon Weapon chart). Combined with 2+/3++ (possibly re-rollable, if you have Warp Fate), and this makes for an exceptionally dangerous, hard-hitting unit that can deal with everything from Imperial Knights to TWC to enemy MCs to even hordes of light infantry. Even more important, you opponent cannot ignore this unit, because of its mobility, firepower, and close combat potential, but he also can waste a ton of his combat power trying to stop it unsuccessfully, provided you have at least one Blessing activated on the unit. Don’t forget, you can also break off the Lord and Exalted Sorcerer to assault other units, if you need to, or just keep them altogether to maximize the synergy and keep everyone Fearless as well.