The Ascent uses a very interesting cover mechanic, where you can shoot accurately from behind cover by lifting your weapon and aiming higher. Due to the game being isometric, you can crouch behind cover and kill enemies without suffering from any aiming penalty.
This Aim High mechanic is the key to make enemies stagger. Every enemy has a stagger gauge that is underneath the health. It's represented by a yellow bar. Call it their composure. Once this gauge is full, they will stagger, meaning they cannot attack or move until they regain their composure. Allowing you to rain bullets on them in safely.
Related: Can you sprint in The Ascent?
If multiple foes assail you, you can slow them down a touch by shooting them in Aim High, allowing you to thin out their numbers before they reach you. This can be done behind cover, so enemies' gun fire cannot hurt you either.
To Aim High, you hold down the Left Trigger or hold down Right Click. The stagger gauge only increases if you are Aiming High. You don't have to do this to kill enemies, but using Aim High causes as much damage, and it staggers enemies, so there is no reason not to use it in every circumstance. Just be watchful of enemies crouching, as this will not affect them.
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