Then if cast from exile you'll also gain twice that power's life - great for saving yourself and then free in Type Four where you have infinite mana but just one spell per turn barring alternate costs like Force of Will or this
Evolving Wilds FTW Creatures (11) Zof Shade x2 Indulgent Tormentor Stormtide Leviathan Jorubai Murk Lurker x2 Gravedigger Necromancer's Assistant Gargoyle Sentinel Witch's Familiar Wall of Frost Instants (5) Lightning Strike Negate Dissipate Unmake the Graves Flesh to Dust Sorceries (4) Festergloom Divination Covenant of Blood Sign in Blood Enchantment (1) Lands (19) Evolving Wilds x3 Mountain Island x7 Swamp x8 As Reid Duke himself describes here in greater detail, this was an unusual decision that he attributed to his high mana curve, several mana sinks, solid density of card advantage, and light red splash
Unlike many planeswalkers the ultimate on Ajani creates a secure lock on the game, and thanks to the protection Ajani's ability gives, it is practical to get there even against decks capable of attacking
Each Pietra you control knows what jokes you've told that game, even if that Pietra wasn't under your control when you told that joke
If it were printed in the main set, Id say it could have gone down to bulk prices, at least for now
You See a Guard Approach