Elemental damage build for [Broken War]:

This is a low complexity build that can be easily constructed after completing The Second Dream. [Pressure Point] and [Fury] are used to boost the base melee damage while Organ Shatterer and True Stee are used to boost critical damage and critical chance. The remaining four mod slots are used for elemental damage mods. The result is a build with very high average damage and sustained damage that can be built early in the game but will remain useful into the endgame.

Pick your favorite Sword Stance mod (you've probably obtained at least one by now), or just button-mash away with whatever stance mod you feel like dropping in. If you're good at combos, run Blood Rush instead of either True Steel or Fury.

This particular build uses viral damage in order to maximize general-purpose utility against everything except Infested. Virulent Scourge / Fever Strike and Vicious Frost / [North Wind] can be replaced with the mods required to generate the desired elemental damage type or combination of types.

An easy 1-legendary-mod upgrade for this build is to swap out [True Steel] for [Sacrificial Steel]. This will increase the average hit damage to 7550.6, and the sustained damage to 9758.5. Swapping out for [Sacrificial Steel] can be done without needing a forma if the stance mod is of the correct type for the slot. However, if you're running [Blood Rush] (as previously suggested) then Formaing will still be necessary.