This build is designed to be as simple as possible, with no Umbral mods and only one primed mod. I didn't want to invest too much into Harrow right now, since his prime should be right around the corner.

• [Adaptation] doesn't need to be maxed. Rank 5 or above should be fine. If you prefer, you could add one more forma and use Rolling Guard. Personally, I don't like that mod, and Adaptation works really well with high shield frames.
• Flow could be swapped out for Primed Flow or Lasting Covenant.
• I like Arcane Avenger, but it's a bit redundant with Harrow, I suppose. An additive 95% critical buff is insane, though :D
• Most aura mods will work, but I personally like [Enemy Radar]. It's nice knowing where your foes are.