The new Aberrus Tier set is powerful in single target and AoE situations
2-set: Gain 1 stack of Stormkeeper every 50 seconds - This triggers within the first 5 seconds of a pull and then every 50 seconds after that. This is a big reason as to why the talents have shifted heavily into the left side of the tree, with this essentially giving us 50% more Stormkeepers throughout a fight. A nice feature of this is that if you currently have Stormkeeper active when this effect is supposed to trigger, it will not go to waste. Instead, it will be delayed in a way that you’ll get it within 5 seconds of spending the currently active Stormkeeper.
4-set: For 8 seconds after you consume Stormkeeper, your Lightning Bolt, Lava Burst, Icefury, and Frost Shock generate 50% more Maelstrom, and your Chain Lightning, Lava Beam, and Earthquake critical strike damage is increased by 20% - This buff is granted after casting the second Stormkeeper charge.
For single target the maelstrom generation helps generate a lot of extra Elemental Blasts, which in turn gives more Surge of Powers that gives you extra overloads on Lightning Bolt that then generates more Maelstrom and so on. In AoE, the 20% crit damage is very strong, and you do get the benefit of this on the overloads from the 2nd Chain Lightning as you gain the buff before the overloads actually happen.
Embellishments are currently at the time of writing this shifting away from the Elemental Lariat and into either the Horizon Stride 2-set, the Adaptive Dracothyst Armguards or the Shadowflame-Tempered Armor Patch.
Horizon Stride consists of the Wind Spirit’s Lasso and the Scale Rein Grips which offer a much better uptime than previously of the haste buff. This set works very well in most scenarios, both AoE and single target.
Adaptive Dracothyst Armguards offer both a Haste/Mastery buff when dealing damage, as well as a Crit/Vers buff when taking damage. These bracers get better the more difficult content you engage with, where you're able to reach upwards of 35-40% uptime on both buffs, providing a massive amount of stats.
The Shadowflame-Tempered Armor Patch is stronger in a single target scenario but scales fairly poorly into AoE. tt is however more flexible and can be recrafted onto mail armor from season 1, not jewelry of weapons. This makes it an excellent choice if you’ve ran out of sparks and are unable to craft the Horizon Stride set. The embellishment stacks so it can be added to two pieces of armor.
Elemental Lariat is by no means bad and can still be used for as long as it takes to transition into either of the above choices.
It’s worth mentioning the Acidic Hailstone Treads as they are performing very well in sims, but the 10% movement speed loss is pretty rough for a spec that’s fairly immobile. Use at your own risk.
My personal recommendation, given the number of single-target encounters in the current raid, is either Adaptive Dracothyst Armguards + Shadowflame-Tempered Armor Patch or two of the Shadowflame patches. If you primarily engage with Mythic+, the Horizon Stride set is the better option.
The best trinket this tier is, by far, the Ominous Chromatic Essence, assuming you have enough people in your raid to cover all the different stats. It's still the best with just a few of the different buffs.
Vessel of Searing Shadow is another great trinket from the raid that provides a solid amount of haste with the occasional dot. This is an excellent second choice that works in every scenario.
Rotcrusted Voodoo Doll, Naraxas' Spiked Tongue, Idol of Pure Decay, and Spoils of Neltharus are good alternatives from M+. The Voodoo Doll is better than the Vessel of Searing Shadows if attained at the maximum ilvl of 447 from the weekly vault.
Whispering Incarnate Icon remains a very strong option but falls off as your healers and tanks stop using the trinket.