In my Depths deck, I run 4x eidolon of rhetoric since the misstep restriction. When the card lands, it wins games. If I can turn 1 stick it, I usually beat PO and xerox that give my deck fits. The problem is I often only have 1 or 2 mana on turn 1, and then lose before I get a turn 2 vs something like PO. This shaves that effect's cost to 1 mana (and can't be plowed) - this is a welcome addition to my deck.
This card is basically good in any deck that wants to build a 50-card-or-less deck (4x this, 4x wraith, 1x git probe, X cantrip). In decks that want multiple pieces or several options, I think this card is just 4 less spots for gas. Keeping a hand with this as your first or second land drop, hoping to see one in the top 5, is almost always worse than just mulling. The times you use it turn 0 and wiff on a land you wanted, it will cost you games.
@cutlex This makes no sense to me. Shops was tier one and borderline oppressive before WAR came out. Now after WAR and M20, they have +1 Karn and +1 Forge...and they drop to tier 2?
Edit - I'm late to the party. I read further and saw several folks said this exact same thing!