I have 35 ppl on my friends list who beat all UN trials and 15 of them have done all UN trials without scythe (DS,Bota,claws and kg)
Some of them have youtube channels that you can check out (showr18, Los Kuz, Modded Skill) they are very good ^.^
I myself have so far only done UN1. 2, 4 and 6...