Its casting cost is less restrictive, it can go in a wider range of decks, and it doesnt have flying, so it dodges one type of removal (albeit not the most popular)
Given the fact that Deadpool is a fourth-wall breaking chaotic character, completely self-aware of his existence as a fictional character, this is to be expected
When you cast it for its prototype cost it becomes a three-mana 1/3, which in a set with tons of Powerstone ramp but very little ramp elsewhere, can prove vital
Phyrexian Tower If you have sacrifice fodder lying around, Phyrexian Tower becomes one of the best lands in the format
Whats your favorite way to untap lands
Its just shorthand for an additional mana cost you can also pay by tapping your artifacts or creatures