It is recommended to replace Aegis Storm ([Hildryn]'s 4th ability) with Voracious Metastasis in this build since Aegis Storm is more of a gimmick than anything. The energy orb generation that it gives from airborne enemies is nice for allies, but the buff you'll be giving to your allies is far more powerful and consistent. For your own energy/shield generation, Pillage should be plenty for any needs that you'll have.
This build gives all allies within 50 meters upon Voracious Metastasis activation a massive 49.8 energy per second for 15.55 seconds for a total of 775 energy.
Voracious Metastasis ability breakdown:
The ability drains energy from [Hildryn] to give that same amount in the form of energy to all allies within the range of shared affinity (50 meters) and rewards Hildryn with a large amount of health regeneration.
Lower ability efficiency to increase the shield drain, directly increasing the energy distribution to allies.
Increasing duration will decrease the amount of energy per second given to each ally.
The health regeneration is rarely relevant, but it is the only part of the ability affected by ability strength.
The range can be increased from 50m to 200m with the use of Fosfor Rahd or Fosfor Blau, which are obtainable as blueprints from Nakak on Cetus.
How it works:
Keep Haven active as often as possible while frequently activating Pillage when near enemies to keep your shields high. Activate Voracious Metastasis whenever the buff falls off of your allies to keep them happy and able to spam abilities.
Note: Voracious Metastasis cannot be applied to allies who have an active energy-draining effect, such as Gloom ([Sevagoth]), Peacemaker ([Mesa]), Danse Macabre ([Revenant]) and others. Coordinate with your allies to ensure that you're able to keep the buff on them when they need it most.
Index Note: Since carrying points in the Index will decrease max shields and health while also draining energy(shields in [Hildryn]'s case), holding any large amount of points can be very dangerous. Holding 10+ points will require you to Pillage on a regular basis. If not, the points will make it nearly impossible to activate abilities since it will drain your shields all the way to 0 in a matter of seconds.