Light Attack Lucy works as the name describes. Keep light attacking until you win!

Sets:
Molag Kena x2 1 heavy 1 light. (haven't switched out for medium or heavy, I prefer 2 heavy but whatever works) (Impenetrable with 1 Magicka enchant and 1 Health)
Spell Strategist x5 all light armor (all divines and Max Magicka Enchant)
Queens Elegance x5 weapons (both infused with Decrease Health Enchant) and jewelry (arcane with spell damage enchants)

Rotation of this build is quite simple. Before the fight apply Boundless Storm and Critical Surge and light attack 2 times to proc Molag Kena. Switch to front bar and use Rune Cage on your preferred target, then Elemental Weapon. After that I usually light attack 3 times before reapplying Elemental Weapon again, to save on Magic. Any time Crystal Fragments procs I use that for a quick high damage burst. When the enemy gets low on health I apply endless fury and keep light attacking until death. Overload makes a great ultimate to use when you feel you are going to be overwhelmed, but at times Atronach is great for the stun. For healing I double down on Dark Conversion and Clannfear. Dark Conversion also doubles as a great source of magic regen.

This Build pushes just over 5k Spell damage and on some weaker targets it only takes 3 or so hits to kill. Its a really fun build thats a little out of the ordinary but a great build to learn the nuances of pvp, enjoy!