Play design is the new development team, and they attempt to balance everything
On the upkeep, Mirror Universe's controller may tap and sacrifice it to swap life totals with their opponent
Sure, their commander can have hexproof or shroud, but chances are high the equipment will not
Library manipulation, such as fetchlands and Sylvan Library, will also be a great help to make sure creatures are on top of your deck
The only problem with trying to utilise Shift as an ability is that it relies on you taking up space in your deck for cheaper versions of the characters you want to shift out
In theory, you can balance out the mana loss by playing two lands on the following turn, but if Zell gets removed youll be left down a land and in a very nasty spot