The Ultimate end game [Valkyr] build, personally i think this is the best Warframe in the game.

This build, paired with my ULTIMATE Talons build and other buffs can shred anything. Acolytes? no problem, 1-2 hits and they are dead. Archons? shreds through their damage reduction like butter. New Fragmented boss? well, it wont kill it fast but effortlessly, since the boss has some new DR type.

What school to use? IDK i prefer Madurai for the 40% strength boost, or Zenurik for 20% strength and energy from wellspring. You can use whatever you want tho
Archon shards? ALL PURPLE shards for melee crit damage, cause it doubles when over 500 energy

Also for melee stat stick, equip all gladiator mods you have, for the extra crit chance

ALSO, equip Arcane Dexterity on all weapons for the bonus combo timer

Fell free to suggest anything since the build is not perfected (but IS perfect), I use it in almost every mission till I get bored so yeah its pretty