As Magic’s Great Designer Search 2 surges along without us, we can continue making our own cards for the hypothetical Robot Viking Magic set. Mastery of the Mind seems simple (and powerful) enough. What I want to discuss is the proper costing of this card.
The effect is pretty straightforward and obviously pretty powerful in certain situations. Seems like a good candidate for a rare. Pinning down the proper mana cost is difficult, though.
We can start by looking at the baseline modern mana cost of blue card drawing spells. The standard is Mind Spring (although it isn’t currently in Standard at the moment). To draw three cards with Mind Spring costs five mana, and four cards would cost six. Mastery of the Mind, as I have costed it, can potentially net you three to seven cards for four mana. Seems like a great deal, and a major power upgrade over Mind Spring based on that.
However, Mastery of the Mind has a big drawback — it only gets you larger numbers of cards in certain situations. Worse, those are the situations when you least need to draw lots of cards. When Mind Spring is the last card in your hand, you can spend nine mana for a full seven-card refill. When Mastery of the Mind is the last card in your hand, it won’t give you anything at all. It’s a terrible late game topdeck. And even if you do play it for a full seven card draw, you’re probably going to have to discard most of them at the end of your turn.
So we can see that the optimal situation for casting Mastery of the Mind is when you have four of five cards (including Mastery itself) in your hand, which will draw you three or four cards (since Mastery leaves your hand when you cast it). It’s a very efficient card draw spell in those exact situations.
Now the question becomes, is four mana too much for such a situational card? Could this be made a three mana card considering you have to wait for the right moment to use it? And considering the amount of time it will be a dead card in your hand? The answer probably comes down to what kind of set you want to build. I don’t think it’s broken at three mana, but it’s a massively powerful card that people will build decks around. At four mana, it’s still good. I’m leaning toward four.
One other thing to consider: what if it was an instant? Huge increase in usefulness there, which might necessitate bumping it to five mana. I prefer it as a sorcery, but it’s open to debate.