My personal take on the raw damage [Torid] incarnon.

• Saryn exclusive gas variant *

With nearly instantaneous stacking of primary [Frostbite] from nil to max and a massive crit multi of 10.5x , this supposedly meme build preforms very well up to around the level 2000 mark (haven't taken it higher) with external sources of viral such as a panzer vulpa, a nourish subsume or even better - armor strips.
[Vile Acceleration] can be swapped for [Primed Shred], if higher chaining range is needed, but we're looking at over 30k dps loss and having to pop another forma.
For a more traditional viral/slash approach (while keeping the polarities unchanged) [Stormbringer] is replaced with [Hunter Munitions], primary [Frostbite] with primary merciless, while [Malignant Force] remains open as a flex slot, personally i'd put [Hammer Shot] in there, or even another forma for [Galvanized Scope] if you can be bothered to aim for headshots.

For a basic riven, which will replace vital sense, we're looking for something with multishot and either crit damage/chance, if you can afford it - multishot and both crit mods. Rolls don't need to be gg to explode the output of this thing.

For evolutions go for Final Fusillade > Swift Deliverance > Survivor's Edge (if you're planning to have a viral/slash config on swap, if not - use the pure crit chance evo)

edit:

Q: "OMG why not primary merciless, why not primary deadhead, numbers go brrrrr wtf?!?11?"
A: Well, i wanted to make a, you know, FROSTBITE Torid, and i did, if you don't like it - don't use it, slot whatever in the arcane slot and pretend anything except viral+slash matters.