Welcome to my Nightblade Healer build! It's still a work in progress, but hopefully you'll find this useful and enjoyable. Using this build, I've been able to heal vet DLC dungeons and vet trials.
Enjoy!
Gear:
Symphony of Blades: probably the strongest healing monster set in the game. It's great for sustain. Alternates include: troll king, earthgore, and, if you need more sustain, engine guardian.
Grand Rejuvenation: This procs increased resource regeneration on casting grand healing.
Master Architect: Procs major slayer on ult for a percent of the ult cost. If you use warhorn, you get major slayer, major force, and buffed sustain. That's a great combo.
Olorime: This procs major courage, buffing the group damage.
Alternate set Stone-talker: This is probably the best five-piece set for group sustain this patch.
Note: perfected gear only provides a slightly larger magicka pool than non-perfected gear
Alternate Non-trial gear:
Hollowfang: This is a decent sustain set with some built in healing. Not as good as Stone-talker, but quite solid.
Spell Power Cure: Arguably better than Olorime in some situations, this procs major courage on overheal.
Beginner gear:
If you're new to ESO and/or healing, Sanctuary and either Winter's Respite or Worm's Raiment make a good starting point, with Troll King as a monster set.
Backbar weapon: You can run either ice or lightning, depending on your preference and your group's need. As for enchantments, crusher, magicka drain, or a damage glyph all work.
Quick note on CP: the green CP have no effect on combat. Choose what you will there.
Frontbar run through:
1-3. Radiating Regeneration, Combat Prayer, Healing Springs. Basic healing staff abilities. Cast 'em often. Make sure to keep Combat Prayer up for minor berserk.
4. Funnel Health: Nice HoT, this is a bit of a flex spot, you can use what you like here. Options include: Syphoning Attacks, for sustain; Dark Cloak, for healing and minor protection; Mass Hysteria, for crowd control;
5. Healthy Offering: This is your Nightblade burst heal.
Backbar run through
1. Overflowing Altar: Strong burst heal option.
2. Wall of Elements: Important debuff. Can use ice or lightning staff, IMO.
3. Elemental Drain: Procs Major Breach and Minor Magickasteal. You could consider running Debilitate here, but that doesn't proc Major Breach, so it's the inferior option.
4. Refreshing Path: Nice healing AOE that also grants Major Expedition
5. Energy Orb: Very important for group sustain, as NB healers don't get great synergy options.