Notable GlyphsWith Drain Soul as Affliction.While in a Demon Form as Demonology (either Meta or DA).With Chaos Bolt or Shadowburn as DestructionYou gain 20% of your total health. Note that you have to land the killing blow with the above conditions, if your minion or a party member kills your target you do not gain health.
The following glyphs, mostly major with a couple minor, have an impact on gameplay. Most of the minor glyphs not listed are either cosmetic or don't have a significant gameplay effect.
Glyph of Dark Soul
This glyph grants you 10% of your Dark Soul’s buff when your Dark Soul is off cooldown, but it reduces your Dark Soul’s buff by 10%. Bear in mind, that’s 10% of the buff not 10% haste/crit/mastery. So, with this glyph active, you gain 3% hit/crit/mastery when Dark Soul is off cooldown, 27% for 20 second when you use it, and 0% while it’s on cooldown.
In general, this glyph is a DPS loss for sustained damage when Dark Soul is used whenever it’s cooldown is up, and a burst DPS loss when you’re saving the cooldown for something important. So, where is this glyph useful? There are two specific situations.
One, if you need to both do high sustained DPS and you need to save your Dark Soul for burst, and you need to hold on to Dark Soul for a period of time between 20 seconds and 2 minutes. Two, you don’t want to use your Dark Soul because it’ll get dispelled (or stolen), but you want to at least gain some benefit from it.
Glyph of Demon Training
I go more in depth on this glyph in my Primer: Minions, Guardians, and Level 75 Talents, but essentially this glyph makes your demons a bit better. It has no impact on demon DPS, but for a couple of them it does improve survivability a bit.
Glyph of Demonic Circle
Reduces the cooldown of your Demonic Circle: Teleport by 4 seconds. Not a huge amount, but definitely useful in situations where every second counts.
Increases the duration of Corruption and Doom by 50%, but reduces their damage by 20%. For the most part, this glyph is a DPS loss. You do save some GCDs with the extended durations, but that isn’t worth the damage loss. Mostly, this glyph is for newer players who aren’t as capable of handling their DoTs perfectly. On an interesting note, with this glyph and Pandemic you can get Doom up to a 2.25 minute duration.
Your Fear no longer causes the target to run around, but Fear now has a 5 second cooldown. Mostly, this glyph is used for PvE crowd control, where a target runng around is liable to pull extra groups. Interestingly, this glyph does not add 5 seconds to Blood Fear’s 10 second cooldown.
Your healthstone now heals 40% of your health, but it’s over 10 seconds. This glyph only affects your healthstone. The increase in total healing is nice, though whether or not it’s worth the cost of having immediate healing depends on the situation.
Glyph of Life Tap
Instead of consuming health, your Life Tap places a healing absorb debuff equal to 15% on your health. The debuff lasts 30 seconds, and repeated Life Taps both refreshes it’s duration and increases the absorb amount. The debuff’s absorb does not have any practical limit, you’ll need to either get healed for the amount or let it drop off.
This glyph does not directly increase or decrease Life Tap’s cost, it just changes it into a different form. In either case, you’ll need to be healed for 15% of your health per tap to get back to normal. The glyph does have a small advantage in that if you do not need to be healed for it’s duration you essentially get a free Life Tap, but situations like that are going to be uncommon outside of soloing. It’s also a good idea to keep your healers informed if you decide to take this glyph so that you don't get put into a situation where you’ve accumulated a sizable debuff and suddenly take a damage spike.
Glyph of Siphon Life
This glyph heals you for 20% of your Corruption or Immolate’s damage. This is a fairly decent amount of healing, but it’s slow and constant, and it obviously depends on whether or not your DoTs are ticking. If you don’t go for the talent Soul Leech, this glyph is a decent substitute to pay for your Life Tap health debt.
Glyph of Soul Consumption
This glyph changes based on your spec. If you kill a target that yields XP or honor with:
Glyph of Soulstone
This glyph increases your target’s health when ressed to 100% instead of 60%.
Glyph of Eye of Kilrogg
This minor glyph has several different effects. First, your Eye of Kilrogg can now fly in areas that allow it, but it loses it’s stealth. Second, it’s move speed is increased by 50%. And third, when you cast Demonic Circle: Summon when your Eye of Kilrogg is active, your circle is placed at your eye’s location instead of yours.
Glyph of Health Funnel
This minor glyph changes your Health Funnel from a channeled spell into an instant 15% minion heal with a 10 second cooldown. Though the total healing is lower, the ability to instantly heal your minion with only a minor loss in sustained DPS is pretty valuable. This glyph does not function if you talent Soul Link, and it prevents the use of Soulburn: Health Funnel for Affliction.
Glyph of Curse of Exhaustion
This glyph increases Curse of Exhaustion’s snare effect from 30% to 70%, but it halves the duration and adds a 10 second cooldown, which prevents it from being spammable. This glyph does not prevent the use of Soulburn: Curse of Exhaustion (even if CoEx is on cooldown), which applies the 30% version of the curse in an AoE.
Glyph of Soul Shards
This glyph increases the number of Soul Shards you can have from 3 to 4. Since Affliction can easily start a fight with a full load of shards, this glyph essentially grants you one extra shard at the start of a fight. Additionally, it gives you more room to pool shards without wasting Nightfall procs. If any glyph is a must-have for Affliction, this one would definitely be it.
Glyph of Soul Swap
This glyph changes your Soul Swap so that it does not consume the DoTs on you current target, but it still copies your DoTs onto a second target. This effect adds on a 30 second cooldown. Soulburn: Soul Swap will not function while Soulburn is on cooldown, but otherwise should work fine. This glyph makes it easier to DoT up two targets, but it limits your ability to effectively target swap.
Glyph of Unstable Affliction
This glyph trades UA’s silence on dispel for a guaranteed crit that hits both the target and the dispeller.
Glyph of Demon Hunting
I go over this glyph more in-depth in Primer: Demonology Specialization, but suffice to say that it adds a second demon form, Dark Apotheosis, which provides some defensive utility and some minor tank abilities.
Glyph of Imp Swarm
This glyph gives you the ability Imp Swarm, which instantly creates 5 Wild Imps on a 2 minute cooldown (reduced by haste), but it increases the cooldown on the Wild Imp passive to 24 seconds (reduced by haste) and prevents Wild Imps from proccing while Imp Swarm is on cooldown. Essentially, you’re trading a passive, stable proc for a strong cooldown. Imp Swarm’s DPS contribution varies depending on the fight’s length. For example, if a fight lasts 2 minutes, you’re only going to get 5 Wild Imps out of Imp Swarm, whereas you’d normally gain 6 without the glyph (ignoring haste in both cases). If the fight lasted 2:20, you’d gain 10 Wild Imps from Imp Swarm, where normally you’d gain 7 Wild Imps. Over an infinite amount of time, the glyph would come out to be a DPS loss, but all fights are finite.
Glyph of Shadowflame
This glyph increases the snare on your Hand of Gul’dan’s Shadowflame debuff from 30% to 70%, but removes HoG’s stack mechanic and gives the ability a 15 second cooldown. Normally, you could stack the debuff for twice the damage and a 60% snare, but it takes 30 seconds to generate the two charges necessary to do that. The glyph allows for a stronger snare in half the time, though it is no longer capable of higher than normal damage.
Glyph of Carrion Swarm
This minor glyph removes Carrion Swarm’s knockback. Useful for PvE, where you typically want to keep your targets clumped up.
Glyph of Falling Meteor
With this minor glyph, when you use Demonic Leap while falling, you’re fall speed will increase and you won’t die to fall damage. You’ll still take fall damage, but you’ll end up with at least 1 health.
Glyph of Hand of Gul’dan
This minor glyph allows your Hand of Gul’dan to be manually targeted instead of automatically targeting your current target. This can allow you to fudge the area and potentially hit more targets than you would otherwise, but your HoG will no longer track moving targets.
Glyph of Burning Embers
This glyph increases your Burning Ember pool from 3 to 4. Unlike the Glyph of Soul Shards, this isn’t quite a must-have glyph. It’s very useful if you’re planning on pooling embers for burst, but if you prefer spending embers ASAP you aren’t going to get much use out of this glyph.
Glyph of Conflagrate
This glyph causes your Conflagrate’s snare to work on a target even if they don’t have Immolate up on them. It’s a pretty nice utility, though it’s obviously not going to be useful if you can’t snare your target, or if you don’t really care if they’re snared.
Edited by Fallensaint on 9/24/2012 9:27 AM PDT