It's a powerhouse of mana making, and unlike devotion, this will count tokens you chose too as well as dorks you cast
In the Artemis Fowl short story "LEPrecon", Holly plays a game of Paintball with the commander about her promotion, where the commander promised her she would win if she managed to land a single hit on him
This cards ability to act according to tempo at any point in the game with some fairly average effects gives it a reasonable spot
K'rrik himself costs seven mana, but three of that cost is Phyrexian black mana
At the very least, Id invest in a Gravecrawler, since it so easily comes back from the graveyard and can be sacrificed to Gisa over and over
Special Guest cards are found in Playbooster MH3 packs and Collector boosters