Power level wise the card fits in just right in Modern, as there are a lot of threats which go under the card, and cards like Veil of Summer and Cavern of Souls give slower creature/combo decks enough counterplay against it
I give this precon commander high marks for giving evoke to cards that were never intended to have evoke like Grave Sifter and Shinestriker
Standard has access to quite a few pieces for a Soul Sisters deck such as Lunarch Veteran, Cleric Class, Trelasarra, Moon Dancer and Cleric of Life's Bond
But a one-time Necro for 5 mana with the same restriction to cast on end step is surprisingly difficult to use, which is of course the point
Crosis, the Purger is in great colors to be running discard strategies, and its significantly better than Darigaaz, the Igniter, which deals damage according to that colors presence in their hand