Way back when Avacyn Restored was released, I recognized right away that Zealous Conscripts was a rather powerful card. A 3/3 creature with haste at five mana is decent on its own, and adding in an Act of Treason—one that snags planeswalkers, no less—just added some huge upside. It probably would have gotten a little more hype than it did had it not been part of an Intro Pack.

Of course, the fact that it was an intro pack means that the card started at a dollar, and so I started picking them up in trade. Before long, the card was topping out curves in aggressive red decks and acting as another powerful creature for Standard RUG Birthing Pod decks. Its subsequent spike to $5 validated my initial assessment of the card, and I felt damn proud.

Soon enough, the card started seeing play in Modern RUG Birthing Pod decks, too, acting as a five-mana combo piece to go with Kiki-Jiki, Mirror Breaker. I sold a bunch of copies at the peak price, but I held even more believing that being both Standard and Modern playable would lead to an even higher price. As the card dipped through rotation, I held onto a couple last playsets...which now reside in my bulk box.

Going for an Intro Pack rare was my first mistake. My second was not paying attention to the fact that it usually was not a four-of. I was only beginning to get into MTG finance at that time, so it's easy to see these obvious mistakes in retrospect. But most of all, the problem was that it was a large set rare in a set with lots of cards that were high in value.

Khans of Tarkir is similar. You might be looking at a particular rare that is obviously powerful, is already seeing play, and/or has a nice buy-in price. By all means, take these opportunities when you think you can make a profit. But learn from my mistake: sometimes a card can be good in multiple formats, but the sheer number of copies on the market will keep it from ever going too high in price. I've learned the hard way over the last couple years not to be too greedy. When you have the opportunity to sell out and get profit in hand, remember that a card's power level is not the only thing that determines its price. Keep this in mind as Khans of Tarkir cards start their inevitable declines.