General Thoughts
Shadow Priest is receiving a set bonus focused around two of its lesser used spells in 10.2,
Palabra de las Sombras: muerte and
Palabra de las Sombras: dolor. Both of these spells are core parts of Shadow Priest's kit but have for various reasons generally been less relevant or effective so far in Dragonflight. The introduction of talent trees has seen
Miseria's position shifted from being a choice talent to something that is pretty much free to pick up for all builds of Shadow Priest, allowing
Toque vampírico to apply
Palabra de las Sombras: dolor has meant that
Palabra de las Sombras: dolor was only used in the most dire of circumstances when you had to move and had no better option to fill the global.
Palabra de las Sombras: muerte however hasn't really felt like it's had a kick since Warlords of Draenor, and has either been a resource generation tool in a much more diluted resource pool or just a slightly harder hitting
Explosión mental. Personally I'm happy to see a set bonus that aims to allow these two spells to stand on their own within the rotation and actually hit hard.
Relative Strength
Looking at initial numbers and how it compares to other set bonuses this time around, yes. Shadow's set bonus looks very strong at least for Single Target, mostly thanks to the 2set bonus and its interactions with
Portavoz de la muerte and
Tormento ineludible, this also gives it some AoE value although the generally unwieldy nature of
Dominamentes based talent builds in Mythic+ makes this more of something that's powerful in theory than 100% in practice. There is also some AoE interaction in the 4set with the backlash damage you're taking from
Palabra de las Sombras: muerte also improving the potency of
Fragor de las Sombras, which explains the rather left field choice to nerf the direct damage of
Fragor de las Sombras in 10.2. That being said though, I'm wary of Blizzard making changes to the baseline class as a result of temporary power gains.
Talent Interactions
Shadow's talents and their interaction with various types of temporary power is beginning to seem like a broken record. Shadow has two general build ideas in its talent tree, one that is heavily reliant on spawning apparitions and
Ídolo de Yogg-Saron, and one that focuses more on
Dominamentes with
Tormento ineludible and
Ídolo de Y'Shaarj. The two builds had been relatively comparable throughout the majority of 10.1 but due to recent nerfs to apparitions and the removal of the apparition set bonus we've had access to in Aberrus it's clear Shadow will be playing the
Dominamentes focused build once again.
Concerns
My concerns about Shadow's set bonus situation are less focused on where the spec is going and more on what it is leaving behind. Shadow received substantial baseline nerfs to
Apariciones sombrías and apparition focused talents throughout 10.1 due to the interactions they had with the previous set bonus, leaving those talents so weak without the bonus to not offer build variety or substantial competition. Seeing the same type of nerfs to Shadow Crash, though less severe, makes me worry we're going to see the same thing again. With how this set is designed we're looking at a tier of
Dominamentes which some may enjoy and some may thoroughly dislike, especially in Mythic+.
As for the bonus itself, the 2 piece looks the more interesting and engaging of the two making
Palabra de las Sombras: muerte feel really worth pressing, the 4 piece however leaves a lot to be desired in my opinion in terms of design. Something was needed to bring
Palabra de las Sombras: dolor back to relevance and there's a problem there that likely takes more to solve than just a set bonus, but the inclusion of
Fragor de las Sombras feels more like an add-on to give it scaling in AoE. The design of the 4 set is also at odds with how
Fragor de las Sombras is typically used as it's a spell the spec relies heavily on in Mythic+ to apply dots and isn't something you can hold for an opportune burst moment while you let your stacks ramp up.
Fragor de las Sombras is also already pulling a lot of weight in Shadow's AoE rotation and adding yet more value to it will likely make the moments when tank movement or awkward geometry cause it to miss even more frustrating than they already are.