At least one Art Rare (AR) or higher for every card
Some players also use it in frog decks for flavor reasons, even though Sab-Sunen doesnt have the frog creature type
At the same time, maybe Gaeas Blessing is better because I can get everything back for free if I surveil it, and it doesnt require as much green mana, but it also doesnt let me choose to only put some things back
After sideboarding, its often the second, third, or fourth wave that overwhelms the opponent, and the Phyrexian spells sacrifice the speed and power of those waves to maximize the first, while the cantrips ensure that your backup arrives in a timely fashion
Originally printed in 2012s Return to Ravnica set, Trostani costs two green and two white mana for a 2/5 legendary dryad