yeah but it's about that wall that costs X to cast (Shifting Wall) i belive something like that, it gets X/X +1/+1 Counters where X is the ammount of mana you payed (its a wall) then unnatural selection, and it can attack, also in draft, i got a unnatural selection (i was playing U/B/R) and i have 4 of the drake that can bounce a kavu, i was going crazy with it
Unnatural Selection has many wonderful uses - The sideboard of a Fish deck loves using it against other theme decks (See that Goblin Lord? Right, your Goblins are now Idiots, and my Fish are Goblins. ). That by far my favorite creature type card of all time.
I made a deck once that used unnatural selection with pure reflection. When ever somebody played a creature I would turn my opponents creatures into creature type reflection, which caused them all to be destroyed by pure reflection.