Blizzard released their second build of 5.2 to the PTR tonight. No ability changes for Shadow have been released; however, T15 set bonuses have been revealed! They are:

• Priest T15 Shadow 2P Bonus – When your Shadowy Apparitions damage their target, they have a 65% chance to extend the duration of your Shadow Word: Pain and Vampiric Touch, causing each to deal damage one additional time.
• Priest T15 Shadow 4P Bonus – Periodic damage from your Vampiric Touch has a 10% chance to trigger your Shadowy Apparition.

These are interesting set bonuses to say the least. A 65% chance on Shadowy Apparition dealing damage to increase the duration of Shadow Word: Pain and Vampiric Touch is effectively an improved version of the current T14 4P Bonus (+1 tick to Shadow Word: Pain and Vampiric Touch).

This chart assumes 8 ticks Shadow Word: Pain as a baseline (SWP+2 @ 8085 Haste; OR SWP+2 w/T14 4P @ 6652 Haste) and does not count proc’d ticks procing more ticks (yo dawg…). To get, on average, at least 1 proc of this set bonus you would only need ~16.9% Crit to have a chance of at least 1 proc occurring or ~6.9% Crit if you are also using the T14 2P Bonus. Moving from T14 4P to T15 2P will be an immediate upgrade, even without factoring in increased stats. These values figure 14% Mastery — if we assume 30% Mastery then the Crit% required is (roughly) 14.9% Crit and 4.9% Crit w/T14 2P; for 40% Mastery the Crit% required drops to ~13.9% Crit and ~3.9% Crit, respectively.

The 4P bonus is also intriguing because it grants Vampiric Touch the ability to spawn Shadowy Apparition at a base of 10%. Mastery will increase the effectiveness of spawning Shadowy Apparition, however it will be quite weak in comparison to spawns from Crits from Shadow Word: Pain ticks.

The number of Shadowy Apparition spawns per Vampiric Touch ticks only increases by 4% from an increase of 26% Mastery — very poor. This translates to less than 1 additional tick, even at 8 base ticks (VT+3 @ 10124 Haste):

This all assumes, of course, that some or all of the existing issues with Shadowy Apparitions are solved, specifically:

• Capping at 3 spawns
• Losing their target and not despawning/heading to another target (keeping other Shadowy Apparitions from spawning)
• Not being able to path to a target because it is flying/too far away

Additionally, it is interesting to point out that the T15 2P works against the current mechanics of Shadow Word: Insanity in that, as procs occur, it will take longer and longer to get Shadow Word: Pain within a range to use Shadow Word: Insanity. This, along with the changes to Power Word: Solace currently making specing in to Shadow Word: Insanity impossible, gives me some hope that this talent will be redesigned as part of 5.2.

…one can hope, at least.

As is common with the PTR, these bonuses probably will change in some way. The 2P bonus seems fairly solid and straight forward, but the 4P bonus is underwhelming to say the least.

[b]UPDATE:[/b] Ghostcrawler has confirmed that Shadowy Apparitions have had some bugs fixed and the number allowed to be spawned at any time increased to 10:

Priest
• Shadow Priests have raised concerns about both of their T15 bonuses being tied to Shadowy Apparitions. Know that we have improved Shadowy Apparitions. Previously, there was a cap of 4 out at once. In build 16446, that’s raised to 5 if you have 2T15. However in the next build, we just raised the cap to 10, which you should basically never hit. And more importantly, we significantly improved their AI. Please try them out. If they give you problems, please be as specific as possible about those situations.

Good news, indeed!