Fetzscrip, the Plane Phaser

Fetzscrip, the Plane Phaser enters the battlefield with a -1/-1 counter equal to the life used to cast it, divided by 2, rounded up
Unlockable
Whenever Fetzscrip attacks, you may pay life equal to its power, if you do, search your library for a creature with a converted mana cost equal to this and put it onto the battlefield, except it is a Phyrexian Horror in addition to its other types