The Fulgurite Fencer - Lightning Melee Build
 Skitarii Build - Warhammer 40k: Darktide 

A Finesse non-Crit Melee Build - "Primitive peoples believed lightning was the providence of the divine. In this, they were correct."

Once an Arc Priest who tired of the cloister — the Brotherhood of Petrified Light does not believe in wasted current.... or talent with a blade....

Mechanicus Power Sword - Your own shard of the Fulgurite, and your primary instrument on the field. Block attack into light spam allows us an easy horde-clear combo. Light special is a quick answer to medium threats, and the heavy special is perfect for dense hordes or carapace with Assassination Protocols and Foe-Render Creed. Weak-spots are desired with Sureshot Cogitator Sync, and  Sunder rewards a properly held strike against stacked carapace through the cleave it grants. The longer the charge is held, the more the current builds behind it- a discipline, not a delay, and Hydraulic Impact protects that opening while you commit to it. Superiority is also great, and a neat trick to remember is you can keep stacks of it up when specialists are far using Noospheric Command! 

Magnicore Plasma Gun - The weapon here matters less than what it's for. Swap freely for the Arc Rifle or Phosphor, so long as it answers for boss damage. Gunsmith is very optional; this isn't a rifleman's build, and you shouldn't be firing enough within a single engagement to need the reload speed. Stepping off the crit path frees up room to experiment, Rising Heat among them.

Voltaic Emitter - Held until stacks near their peak, then released to proc System Shock into a cluster of carapace, or to silence a room of gunners outright. The Voltaic Arcs can also be quite deadly to finish off a threat and play well with System Shock to stack brittleness into entire groups of crushers, turning them into easy targets for your Sword. Overcharge Transfer Lattice stands as insurance against a surprise pack of Ragers or the slow bleed of chip damage. An Arc Priest hoards nothing, not even the ego that you will not be hit. 

Power Overload - The keystone this whole discipline is built around. The steady procs of Critical Power Overload pair naturally with System Shock. Powerdrive is an option but I find de-incentivizes my Noospheric Command but up to you.  Static Capacitor Drain condenses four or five blue nodes into one after five to ten minutes of play, with the nodes on the way here being some of the best in the game, so definitely a severely underrated keystone. 

Artificer Servo-Skull - Here to provide constant stacks of Progressive Plating Matrix, Superior Defence Engrams, and Hybrid Combat Covenant. All while your hands stay on the sword where they belong. Noospheric Command provides you with all the ranged utility you need, leaving the plasma as backup for the rare moment ability charge runs dry. The Medicae Servo-Skull is for clutches and revives, though the ideal engagement never needs it at all. Wasted energy is the only true sin. Being caught unprepared is a close second.