Second, with Eldrazi gone, the format would likely return to the pre-Pro Tour picture which was more linear (bad for a grindy, value combo) and packed with cheap Lightning Bolt-style removal (bad for low-toughness critters like Servant and Teysa)
#1 Mikaeus, the Unhallowed + Puppeteer Clique + Altar of Dementia = Mill entire deck and steal all the creatures and swing with haste
You can effectively double your damage output by swinging in with your army of 1/1 tokens and then sacrificing them after damage for that same amount
Elvish Rejuvenator This card adding a land onto the battlefield is all well and good, but the risk of not hitting anything combined with the remaining cards being shuffled back into the deck rather than going to the grave adds up to too much of a downside
It can clip a Sol Ring and still let you curve out the same turn
Your opponents discards fuel Waste Not and other payoffs while halving their options from hand