Here is a Map I created to boost the Gears 5 achievement "Good Plan, Violent Executed".
Search for Map ID: YJVS91
in Escape mode. If you can't find the map, it is probably to do with the issues with the online services at launch. Try again later.
It has lots of lancers at the beginning, pick them up and saw your way through up to 100 enemies until the achievement pops. Once it does, you can run to the end, past the enemies and the last few sections are a clear run without enemies, so you can get to the exit and close the door without getting flooded with enemies. There is a pile of Salvos on the exit platform just in case you get some enemies that catch up to you.
The video is just a quick run-through of what you can expect, without the sawing. Hope it helps.
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