This build could crush enemy in 1 second even if you play steel path. This build will carry you every stage even stalker at steel path and bosses have no or a little both chance. The red critical will appear at 4x combo multiplier.

Use Power Spike (Naramon Lense) to keep your combo up so you will have red critical every time you hit. This Focus is the focus you need If you play steel path mission.

For the without riven build, you can change both riven and [Organ Shatter] with toxin and cold mod for viral damage. But red critical will start on 8x combo multiplier.