My Main's Build
Great in a group, and decent for non-end game solo pve. This build is not done, and still needs different armor as well as 2 heavy pieces. I plan on getting heavy chest and head. My armor plans are as follows.

Molag Kena 2 piece (head, epaulette)
(Vet white gold tower boss)
+ 129 MG DMG
+ MOLAG KENA ULT (Do to light attacks to gain massive DMG for 6 seconds + 516 MG DMG)

Elegance 2 pieces (ring/staff)
(Sanctum Ophedia bosses)
+ 129 MG DMG

Worms Raiment 2 piece (ring/neck)
(Vet Spindleclutch)
+ 129 MG DMG

Martial Knowledge 5 piece (boots,chest,legs,belt,gauntlets)
(Sanctum Ophedia)
+ 126 MG DMG
+ 126 MG DMG
+ 945 Max Magica
+10 % DMG on second atk

All Base - 639 MG DMG
Enchanted Base- 480 MG DMG
All + Enchant- 1119 MG DMG
Procing Ult- Adds 516 MG DMG for 6 sec after 2 light attacks back to back.
ALL ULT- 1635 MG DMG

MX POTENTIAL= 1635 MG DMG
Not including % boosts or potions.

I still need to get these and then enchant them for max magica and perhaps max health. I also need to respec and take the last 2 heavy armor passives out of my build. I messed it up on mine but it is not shown here. I also plan on taking skill points off the things im not using and perhaps switching regeneration for something like unstoppable (heavy armor skill) but im not certain. Flex spots include Regeneration and Rune Focus. Everything else is pretty much solid.

Disclaimer: This is a test build from a noob to champion rank. So take this build with a grain of salt.

The build is very squishy which is why I plan on adding max health to some of the armor. Also if this is used for vet dungeons I highly suggest eating health and magica food as well as using spell power potions during burn phases of bosses.

How to use this build:

I typically run with the desto staff as my main bar, and use the resto staff as a retreat/heal bar. For the attacks I tend to stack DOT and then hit with one or two shot attacks about twice before switching back. So for this one it would be;

Burning Spear -> Elemental Blockade -> Solar Barrage -> Puncturing Sweeps -> (either repeat SB and PS then loop back to BS. OR Use two light attacks for the DMG buff of Kena then loop back to BS)

Don't forget during a boss's Burn Phase as soon as the boss gets to 40% health spam Radiant Oppression. It gets stronger as he gets weaker. Eventually doing 40k DMG or so a cast.

The timings on this may be wrong as I have not gotten Kena yet and will have to test it then. The exact values of enchant buff may be different as some pieces are maxed at lv 140, so im not sure. I will update this when I know.

For healing I typically do use the Annulment first to keep me from dying before I heal, then switching to Breath of Life. If I have a hard time staying up or just have some extra magica to throw around I do Regeneration and Rune Focus when I have a chance. Also don't forget you can jump back in Rune Focus at the last second to extend its buff beyond normal limits. So for low HP I suggest;

Annulment -> Breath of life -> Annulment

That gives you extra shielding before switching back to the main bar. It may be a good idea to switch one of the flex spots for Healing Ward for extra sustainability in hard battles.

Lastly it may be prudent to switch to Valkyn Skoria since DOT is a main form of DMG on this build. However I'm not sure if it would out DMG Kena for its massive DMG boost. Will need to do more testing. Also for more DOT you could switch a flex spot for Ritual of Retribution if you are good at switching bars, that can give an additional DOT during casting BS and EB. So that would look like this;

Ritual of Retribution -> Blazing Spear -> Elemental Blockade -> Solar Barrage -> Puncturing Sweeps -> (follow previous)