Here’s a non-lethal combo I enjoy putting on The Boss in the final fight of the game. Counter her CQC, equip Mosin Nagant, shoot her in the head, unequip, take her down, equip stun grenade, hard-throw one right into her body, equip cig gas spray, look up to avoid blast, look down and spray her in the face. Rinse/repeat till she’s defeated.

Killing The End early by lethal means at Ponizovje Warehouse Exterior (just after a lengthy cutscene where he’s wheeled out in his chair). Speedy method to eliminate him, though personally not recommended. The fight with him later is a high point of the game and should be experienced. This is a quick fix option if you’re focusing on speed and also to unlock “The Early End” trophy/achievement (don’t forget to grab the SVG at Ponizovje West just before this area).