Am I ready for ultra-bosses?

I am level 100 with only a 10% dmg weapon. I have the basic forge enhancements (working on the good ones) and I am trying to do ultra dage to bypass some grinding for legion revenant.

I have Lord of Order, VHL, Legion Doomknight, Infinite Legion Dark Caster and Archfiend.

Am I ready for ultrabosses and if not, what should I focus on or improve to be able to challenge them every week?