Quantum Theory

Trusty Sidearm
Clear the entire story using only the Revenant.

For this achievement you have to play through the entire game using only the standard weapon, Revenant. On D-Pad press UP.

I recommend to play on easy, it will take about 5 hours, if you are familar with the endbosses.
Dont switch the weapon for an entry playthrough. You cannot play chapters using other weapons and later complete these chapters using only the Revenant. For these achievement it must be a playthrough from the beginning to the very end.
You can also use your melee attack, Filena combo attack, you can use the Filena combo throw and you can also use turrets.

In chapters 0-1 and 0-2 you dont have access to Revenant, so these chaperts dosnt count for that.
You also have to destroy the turrets on top of the gate in chapter 2 by using only the Revenant. So be prepared to save your ammo.