I've never tried to build Mikaeus myself, but from what I know about combo decks there are three categories of pieces that make the deck work: 1) Creatures that can re-undie with Mike's ability
For a card this ubiquitous, it stays remarkably affordable, a couple of dollars gets you a copy
Thankfully, its power is much easier to control in token form
When you or another player rolls a planeswalker symbol on the planar die, the plane thats currently in the command zone is put facedown at the bottom of the planar deck and replaced by the top one
Its proven great in my Legacy deck, but Ive slotted it into many EDH decks as well
Alternatively, you can use it to put your own stuff back into your library, something that might actually matter in this format, where it looks possible to go pretty hard on milling yourself