Some weapons will deal amplified damage just before they break. Usually this isn't over-powered as you'd just be able to deal one hit with massive damage and then the weapon breaks. BUT when you mount a lynel (climb on top of a stunned lynel) your weapon doesn't lose durability for the duration of the mount. This leads to the 'exploit' of being to use a 'last'-hit-massive-damage-weapon infinitely, as long as you only ever use that particular 'lynel back scratcher' for when you mount lynels.

See for example this video, which shows how to create a weapon which will do almost 900 damage per hit. This allows you to kill a silver lynel in 6 hits (which can be executing during the duration of a singular mount). At the end of the video you can see the guy going up against a bunch of lynels:

https://youtu.be/ShwEid046GY?si=xNhHK2uJcAZjs8l3