Onslaught is impossible.

Get 5 Yasuos running the Wandering, Growing, Tempest, and Windwalker augments, more if you're not doing the 4 augments or less mission. It will be a literal fucking breeze.

Well play a couple on captain or onslaught and find some good people. Sadly the only advice I can give you :/ There was a thread that explained how they did it with 2

well, it's not impossible seeing as people were able to do it with only 2 augments equipped... With all 6 it's challenging but not too hard. Just need 5 premades that know the strat you will never do it with randoms

It's possible with 5 competent players, but that's incredibly rare

I've attempted it over 30 times and only beaten it once, with 5 yasuos

Every other game, I have top damage dealt by a ludicrous margin, like 1.5mil with second highest being 300k.