Yakuza Kiwami 2

On the PS4 version of this game, this achievement is slightly misleading in one certain part hoping it's not the case with Xbox One/Win. 10 version (Note: it is the same). The achievement does say you must defeat 100 enemies with weapons however it doesn't mention the most important part. It only counts you defeating enemies with weapons that are in your inventory. So defeating enemies with bikes, benches and other absurd weapons that you find on the street doesn't count so don't rely on the "use weapons to defeat enemies" challenge on the completion list to track this achievement. I got this achievement approximately halfway through the game but if you don't have the achievement by the time in chapter 16 comes around you can get quite a lot of progress here. Before you go talk to Date to say that you're ready for the last battle of the game make sure of at least one of these 2 things. If you have a lot of really durable weapons they'll be great here especially if you have upgraded weapon damage. If you do not have durable weapons clear out your weapon inventory at any Poppo store. The lead up to the last battle will have you battle your way to the Kamurocho Hills construction site from Serena and lots of low health enemies will try to stop you. While you're fighting your way there lots of very durable weapons will be scattered all over the place like Dark Wooden Katana which has a durability of 36 and an attack of 56 or you can find what most enemies will drop items like Chinese Saber which only has 12 durability but has a 72 attack. To make sure these counts if you're a bit worried about that just pick them up and put them in your inventory and then put them to a weapon slot when you're ready to use them. There are several enemies during this part so you'll most likely get a lot of kills during this part.

If you still do not have the achievement by the end of chapter 16 then don't worry. Premium adventures expands the inventory that Kamiyama has to include 3 new infinite durability weapons all of them cost 5 million yen each (Kamiyama is inside the alley across from public park 3 on Tenkaichi Alley after you've completed his sub-story). His infinite durability weapons are Photon Blade RG that does 88 attack and has no effects, Dragon-SP does 100 damage and no effects and the last weapon he sells is Yinglong Tofa that does 88 damage and no effects. You can bring all of these weapons into your Legendary playthrough as well. My personal recommendation from his shop is the Dragon-SP pistol. This weapon makes legendary difficulty and all bouncer missions especially the Amon fights super easy.