You don't choose a target for Selfcraft Mechan's ability at the time it triggers
If you get all three artifacts onto the battlefield, you create a legendary creature tokenthe first time we did thatand attach all three Equipment to it, making a giant, daunting creature
Plus, in a ramp deck (which Green often is, cough, cough) you'll be able to cast big fat stuff like Lifeblood Hydra that can potentially free-cast pretty much anything you reveal
While Kari Zev wasnt an incredible card in terms of power level, it put in solid work here and there, and when it did people saw, and loved, Ragavan
Even if an opponent fires off a Teferi's Protection to save them, you can just create an arbitrarily large Ballista and shoot that player down when they phase back in
9, the Magic: The Gathering Innistrad Remastered Play Booster Box (36 Packs) is on sale for $181.89, down from $251.64 at Amazon