She can either serve as mana ramp, creature removal, or, if you save up for her ultimate ability, you can deal 5 damage to any target every time you cast a spell, which is bound to win you the game quickly
If you're counting on Winged Sliver or Muscle Sliver or any other boost to carry you through combat, then a removal spell on the key ability can destroy your entire team, and even with Hibernation Sliver available such a blow is often crippling
One of the best cards you can run is Retreat to Coralhelm, an enchantment that lets you scry one anytime a land comes into play
Finally, we have Trostani Discordant, a weird card that definitely lives up to its discordant name
If youre running Hashaton, Scarabs Fist as your Commander instead, then Unfulfilled Desires discard effect becomes more valuable