The catch here is that you can just float a ton of mana, resolve Upheaval, then use what mana you have left to deploy mana rocks and threats
The ramp aspect she brings to the table is also very dangerous, as casting turn 4 or 5 World Breakers has been extremely tough to beat
A focused commander makes every card slot more efficient and reduces dead draws
Also, a lot of buylists require you to sort your cards into an exact order (either by set or alphabetically), so "sorting" is a lot more effort than just pulling out high-value cards
We see 5 mana spells that reanimate a thing a lot, and in your typical format, they arent that great
This card is just so, so sick: not only are you destroying an opposing land, youre also rubbing it in their face by going and getting another land for yourself