In the slow but strong Commander format, this can be a game-breaking move for 7 mana
Sporocyst Sporocyst acts like a Farhaven Elf that can get bigger with extra mana, and defender doesnt hurt a card like this too much
Assuming you're playing a bunch of Dragons, defeating the battle shouldn't be a problem since you'll have a bunch of big evasive creatures, although there probably will be times when it's better to just hit your opponent's face and then try to burn them out with the front side of Invasion of Tarkir rather than flipping into another Dragon that dies to a wrath
Knocking someone out with this guy and then sacrificing it for Reveillark is the best
Whether youre answering a Goblin Guide, a Wrenn and Six, or a Signet, this card is an incredibly efficient and flexible removal spell
Commander games tracked on paper quickly become a mess