Brotato PS4 & PS5

What I did to get this achievement:
1.) Ran on Danger 0.
2.) Run six hands, focused on knockback and slows.
3.) Buy wandering bot to slow down the crowd.
4.) I just ran around the outside of the map until the timer ran out, using holes in the group to help navigate.
5.) Also good to invest in HP, HP regen, dodge, to help avoid damage and recover.
6.) As mentioned by others, you don't want to kill anything, as you get both XP and money from the ones alive at the end.

Hope this helps you out!

-Dalfurious

An alternative for anyone struggling with this character in particular, I had a solid run relying on fast weapons and bounces etc but was still no match for the wave 20 boss.

This time, I completely ignored how you're supposed to play this character and instead focused on fast weapons and took damage % whenever possible. By the end of the run my damage was still negative but maybe 4-5 % instead of the base -100% for this character

Not the "right" way to play him but an option for anyone who needs it!