If you and your team have already mastered all dungeon mechanics and done multiple clears the normal way. Ideally, you should have ambush armor first. So after my team learned all the mechanics on RMHM and stopped getting hit and dying, especially since we had a priest with us too, I decided to DPS with my mystic to speed up the runs. Later I found that even without a priest, this can be really viable in any 417 dungeon where everyone knows the mechanics well and so you can afford to be DPSing most of the time.
Weapon
I put double enraged, 6% damage, and CDR. For crystals: bitter, savage, focused, carving. Maybe you will use forceful instead of carving.
Skills
I only glyphed casting speed and HP/MP for resurrecting, since my team dies very infrequently. For now, I just glyphed self-vow and CDR. I also removed the endurance debuff from a volley of curses, since the priest’s plague is better and they don’t stack.(Alternatively, you can remove the 10% endurance buff from the thrall of protection, as it is rather unnecessary with the current console dungeon buffs.)
With these glyph point savings, now I glyphed metamorphic blast and smite damage and CDR.
Armor
I have all ambush with blue power innerwear. I still run HP/HP on my belt (in RMHM) since the extra power from ambush makes it worth it vs. a guile belt with crit/power etc. But maybe if you have a secondary ambush belt you could put crit/crit there or whatever.
Etches
I just have the tier 2 energetic on gloves and wrap, then grounded tier 2 on boots and armor, like normal.
Attack Rotation
Stand right behind the melee DPS players and start off by spamming metamorphic blast until both it and metamorphic smite are on cooldown — the sign of this is your character will be standing motionless even though you are spamming the button. OK, now use boomerang pulse. Repeat this except use volley of curses or something else as necessary any time boomerang pulse is on cooldown.
Results
The result of this I find is that my tank and melee DPS receives as much or more healing than they would if I just spammed titanic favor on all 4 players the whole time, due to the fact that boomerang pulse hits everyone twice and does as much healing as the titanic favor does on each hit.
Also since you are grouped so close with them, the thrill of life is sufficient to cleanse in most scenarios.
Positioning Tips
The DPS players need to position themselves exactly behind the boss to get in the path of the boomerang. However, in RMNM and RMHM, when the “donut” type AOEs hit, you the mystic need to clear out from behind the melee DPS so as not to body-block anyone trying to escape (especially warriors will complain otherwise).
Consumables
I find that Noctenium Infusion makes a bigger increase in mystic compared to other classes. It seems to add 50% more damage a lot of the time, whereas on DPS classes you only get maybe 10% more damage. Maybe I am wrong about this but that is what it seemed like. However, mystic will use up Nocts much faster than other classes due to the fact that metamorphic blast can sometimes hit 5x or more per second and this uses a Noct on each hit. Note, however, I have seen this do 500k per hit of base damage when the boss was enraged, so this damage is not insignificant.
Bravery potion is also the best for mystic since attack speed is the limiting factor on DPS due to how short the CDs are on blast, smite, and VoC. Also, VOC’s animation is long so speeding up that is good.
Thralls
In most 417s, you can also glyph out of thrall of healing and corruption ring, then use the points to glyph thrall of wrath for even more DPS.
Plus, I would definitely put up thrall of vengeance as often as possible. It gets placed about 10m in front of wherever you’re facing. Put it off to the side of most bosses and it won’t get touched, it will just sit there and add its tiny bit more DPS.
If you want to complete your DPS as soon as possible, you can go to U4GM.com to buy Tera Gold before you really start your DPS challenge, everyone wants to get more money in TERA so that they can do more things that they would do, for example, finish all the DPS, that’s really cool.