[Magistar] Incarnon is used to give crit chance and crit damage to Slash Dash (which normally has 0 crit chance and 1 crit damage). Use normal [Magistar] for highest bonuses + riven disposition.

Evolutions
Evo 2: Edge of Justice
Evo 3: Any, eg Orokin [Reach] to help build combo or Swift Break for mixing x12 heavy attacks
Evo 4: Critical Parallel +16% cc and +1x cd

Best used with Magus Aggress. Currently, this arcane gives +300% crit dmg (additive to mods) for both Hammers and Heavy Blades, but does not consume charges when used with a pseudoexalted ability such as Slash Dash.

Why [Primed Fever Strike] + [Shocking Touch]?
While elemental mods do not affect the resulting slash procs, it does provide raw damage for getting through overguard and dealing raw damage to enemies with status cap such as acolytes. If armor stripping, put north wind over shocking touch to create raw viral damage.

Riven - replace shocking touch.
Top rolls: CD/DMG/CC -harmless negative
Other ok rolls: Element (e.g. electric).