Guaranteed to have a good time hanging out with us
Mikaeus, the Unhallowed is awesome for Altar's Reap as well but is even better when combined with Grim Poppet and Rendclaw Trow
I played a lot of it in Amonkhet Standard, I used it in Chaos Drafts to great effect, and it featured in both my Chainer Nightmare Adept and my Burakos/Guild Artisan Rakdos decks
You could certainly play the two of them as partner commanders instead of having Gavi lead the deck
Gaining the ability to swing in for damage the moment your creature enters can be back breaking, especially in the late game when life totals are low
Iona, Shield of Emeria The problem is that this effect easily shuts a player out of the game: it totally stops monocolor players from playing Magic , and even many two-color decks often have a large portion of their hand (and their commander!) rendered uncastable by Iona