Rise of the Tomb Raider

This is a pretty straight forward achievement. First things first do not forget to have the challenge active when you start the adventure. For the easiest experience, I suggest going on adventurer difficulty. From here, look through your cards and make sure you have as many nice weapons and perks as you can (shotgun, bow, outfit, etc.). It is not necessary to use a toxicity card (I did it with solely permanent cards), but if you have some extras laying around, it would not hurt. From here, you can either run around the map and kill enemies or find a branch or high up platform and just camp on that. If you choose a branch correctly, you will be able to kill all the enemies from above with no risk of being hit. The enemies will keep spawning around you as you kill them and you will be periodically swarmed by a large group; this provides ample enemies to take out. When not in combat just use the bow to take out unsuspecting enemies, and once in combat switch to an assault rife or shotgun until all suspecting enemies are dead. Also, if you have not gotten the "Give a Man a Fire" Achievement yet make sure to equip that challenge as well, as the kills with your dragonfire shotgun shells will also go toward the 75 for this achievement.

Keep in mind that you don't really even need a strategy as you could theoretically die an infinite amount of times. I just found this to be the most seamless way of getting this achievement.