Boss specific recommendations and strategy:Raid Bosses
Tier 1 (15)
Fortress of the Mind - The best for single target fights. More insanity generation, and more damage from Mind Blast and Mind Flay. Also synergizes well with the talent Psychic Link and the Talbadar's Stratagem Legendary.
Death and Madness - Can be good in Mythic plus when mobs in a pull dies at different times, and to load up on insanity before the next pack. The biggest downside is that it does substantial reflect damage, which can be dangerous. If your group is doing big pulls this can be a good pick because you basically want to Mind Sear -> Searing Nightmare and not cast Mind Blast or Vampiric Touch, making the other talents considerably less valuable. Death and Madness helps you finish off the remaining mobs after you’re done aoe’ing and will give you a full battery of Insanity for the next pull. Also has incredible synergy with Shadowflame Prism, since chain resetting Shadow Word: Death just gives you more Rifts from the Legendary.
Unfurling Darkness - While not having much value in PvE is the clear winner for PvP - after casting Vampiric Touch your next Vampiric Touch is instant and deals initial damage. Synergises well with both Misery and also Damnation.
Tier 2 (25)
Body and Soul - The best talent in this row. Giving us some much-needed mobility.
San’layn - Would be a great survivability talent if it wasn’t in the same row as our only reliable mobility spell.
Intangibility - Would be a great survivability talent if it wasn’t in the same row as our only reliable mobility spell.
Tier 3 (30)
Twist of Fate - The best talent for pure single target DPS.
Misery - The best talent in spread multi-dotting situations.
Tier 4 (35)
Last Word - You pick this if your group needs more interrupts.
Mind Bomb - Weak pick because it replaces Psychic Scream.
Psychic Horror - Instant single target stun. Very strong pick in both raids (if there are adds to use it on) and M+.
Tier 5 (40)
Auspicious Spirits - Best single target and low target cleave pick. Increases your Insanity generation and the damage from your spirits.
Psychic Link - Strong for spread cleave. Does nothing on single-target. Has been seeing more uses in Sepulcher compared to other raids on a few fights (Pantheon/Rygelon/Lords).
Tier 6 (45)
Damnation - With the introduction of the 4set, Damnation has gained increased value in PvE by increasing the overall uptime of Living Shadow. Currently, it's still slightly lower than both Void Torrent and Mindbender but might see play in certain situations rather than being a dead talent outside of PvP.
Mindbender - In combination with the Shadowflame Prism legendary this is the strongest pick on single target and cleave.
Void Torrent - Strong single target pick if you do not have the Shadowflame Prism legendary.
Tier 7 (50)
Ancient Madness - Can be useful in situations of big AoE where you want to remove void bolt from your rotation while in Void Form. Synergizes well with Searing Nightmare to burst down those big AoE packs in M+.
Hungering Void - The baseline choice for single target and multitarget cleave. You can extend your Void Form by a significant amount depending on your haste and crit. It also makes your void bolt increase your damage done to target for 6 seconds.
Surrender to Madness - This talent gives you a 25 second STM buff, increasing your insanity generation by 100%. It also activates your Void Form for 15 seconds. When the target you cast STM on dies you lose the STM buff but you don’t lose the Void Form buff.
If you can utilize Surrender to Madness perfectly, it can be strong in low dungeons, where the time between pulls are shorter than the cooldown of Voidform (less than a minute). Currently does not see play in most situations.