When you exile a card this way, target creature you control gets +X/+0 until end of turn, where X is that card's mana value
Six Thematically, Im partial to Wrenn and Realmbreaker, but we cant forget about one of the first important bonds Wrenn made with Six
We've also seen Shuko shoot up in value, thanks to its interaction with the absurd Simic value bird, Nadu, Winged Wisdom
Two mana to discard two cards is also just an incredible price, and is especially potent when Hymn to Tourach follows a turn-one discard spell like Thoughtseize or Inquisition of Kozilek
Both legendary creatures also tend to excel in tribal decks, though Ghoulcaller Gisa is a bit more flexible, allowing you to sacrifice any big creature to raise your army of the living dead
That deck utilized Goblin Bushwhacker and Reckless Bushwhacker with Devastating Summons as its combo kill, but the same premise stands here with Goblins