This is my go-to build for Steel Path. It works for solo play or in co-op, hell it even works for eidolon hunting if that's your goal. I don't really think I need to explain how [Harrow Prime] works ability wise but to summarize its pretty simple. Chain, headshot, repeat as needed until target is dead. This build is more geared towards a co-op support build but can be quite aggressive depending on the weapons you use with him.
BUILD SPECIFICS
Archon Shards
The singular Amber Archon Shard for casting speed helps with emergency casts of his first ability and his fourth ability whereas I chose the four Crimson Archon Shards for ability strength to increase the shields restored by his 1st ability and the reload speed buff from his 2nd ability. These choices are personal preference and can be changed if you see fit as the build is solid without them.
Arcanes
Arcane Expertise boosts his shield and overshield capacity increasing his survivability even further
Molt Augmented boosts his ability strength which is great because all of his abilities benefit from this
The arcanes are completely flexible if you would prefer to focus on arcanes meant for headshots or just prefer other survivability arcanes such as Arcane Aegis, Arcane Barrier, or even Arcane [Guardian]. I would however still recommend keeping Molt Augmented for the scaling strength benefits.
ADDITIONAL LINKS
I pair this with the following builds in Steel Path:
Primary - Latron Prime https://overframe.gg/build/632040/latron-prime/ezekiel-1214/
Secondary - Lex Prime https://overframe.gg/build/658449/lex-prime/revelation-2213/
Melee - Dual Keres Prime https://overframe.gg/build/627475/dual-keres-prime/exodus-2224/
Some of the rifle builds I use or have used to hunt eidolons:
Vectis Prime https://overframe.gg/build/626922/vectis-prime/old-hunters-friend/
Lanka https://overframe.gg/build/626938/lanka/eidolons-bane/