Talents & Glyphs
For shadow there's just a few talents and glyphs that I'll point out as being particularly useful:
Divine Insight. This is your one must have talent. Huge DPS increase and often gives you another instant-cast option while you are moving.
Mindbender vs From Darkness, Comes Light: Mindbender brings your shadowfiend cooldown down to 1 minute, FDCL makes your Vamp Touch ticks proc free Mind Spikes. Current math says these talents are about equal but FDCL has the edge. However your rotation is a lot smoother with Mindbender and you can take Mind Spike off of your bar.
Halo. Cool spell and highest single-target dps choice from that tier. You can use an addon to know when you're 25 yards away for maximum damage.
Angelic Bulwark keeps you alive without another cooldown to monitor. I use Angelic Feathers all the time just for zipping around town or catching up to the group in a dungeon.
Glyph of Dark Binding. Allows you to Renew and PoM while in shadow form. Nice for dungeon runs when the healer needs a little help. Great for scenarios - they say you don't need a healer in scenarios but you usually do, and if you're a priest, it's usually you.
Glyph of Mind Flay. Nice speed boost in high movement fights.
Gear
Intellect > Hit (to cap) > Haste > Crit >= Mastery
You do want to reach the hit cap (Spirit and Hit equally effective).
Instructions
Regular Priorities
- Devouring Plague (w/3 orbs)
- Mind Blast
- Shadow Word: Death (when mob is below 20% HP)
- Halo (if you have it, try to be at 25 yards)
- Shadow Word: Pain
- Vampiric Touch
- Shadowfiend/Mindbender
- Mind Flay (stop channeling in favor of a higher priority spell, but fill ALL your downtime with Mind Flay)
On the Move
When you need to move, it's important not to waste that time. You have a lot of instant cast spells that can be cast on the run, so remember to do so. If nothing else, refresh your SW:P while running.
Short Fights / Adds
Multi-dot adds with SW:P and Vamp Touch, use your free Mind Blast when it pops up, and Devouring Plague too (try to hit higher-health targets).
AoE
Only switch to Mind Sear on large, compact groups (5 or more). Do it on a friendly target if possible so it doesn't end early. Use your Halo too.
Other Tips
Do NOT use Dispersion unless you are avoiding some big incoming damage.
You may want to use a mod like TellMeWhen so that you can easily see when your DoTs need refreshing.
A lot of casters lose a big chunk of their DPS to lag. This is quite unnecessary, as there is about a half second during which the server will queue your next cast. So just hit your next spell before your current one finishes.
Helpful Addons
- TellMeWhen - I use this mod for all my dps toons to notify me when to use which abilities.
- Quartz - Shows you the time period during a cast in which you can queue up the next cast.
- HaloPro - Shows you when you're at ideal range for Halo.