So, I was invited to participate in a 5e Lvl 20 One-Shot campaign, with the the core races and classes allowed, and a multi-class restriction by the DM of having to have a minimum of 16/4 in multi-classing (no dipping) [So I could go 10/10, 15/5, 16/4, 12/8, etc]. The issue I'm having is I'm...