Earlier this week, QS founder Kelly Reid pointed out to me that the Return to Ravnica and Gatecrash shock lands appear to be creeping up in price. With spreads at a relatively low 30 percent for most of these, it looks like retailers are having a harder time keeping them in stock since rotation and the new focus on the Khans fetch lands.

As of this writing, Steam Vents is the clear winner here, with both the highest buy and retail prices, as well as the lowest spread (this is personally exciting to me, as I own more Steam Vents than all other nine shock lands combined). It's not too surprising that the UR shock land is the one most in demand at this time. Blue-Red Delver has taken over Modern in a big way, as has Burn splashing blue for Treasure Cruise. In both cases, Steam Vents is a clear need. Don't forget about Splinter Twin, Scapeshift, and Jeskai Control strategies, each of which lean heavily on the Izzet land.

Despite the metagame favoring Steam Vents, the Gatecrash shock lands are a little pricier than their Return to Ravnica counterparts (Insiders can view a full list of shock lands here). This is predictable and expected, given that RTR was one of the most opened sets of all time, whereas Gatecrash was a relative disappointment to many. Fall sets are also drafted longer and naturally hold more interest for Magic players, so you can be sure that there is a much higher supply of Hallowed Fountains out there than Breeding Pools. 

With spreads ranging from 26 percent to 44 percent on the shock lands, you may wonder what comes next. If you're thinking about buylisting your sets, stop thinking that. If you're not aware, a low spread means that a retailer is paying a higher percentage of retail price than for cards with a high spread. High buy prices almost always precede a bump in retail price, which often raise buy prices even further. So now is not the time to sell your Modern lands.

Instead, it may be time to acquire. Most of the shock lands are sitting right about where they were during their time in Standard, but now they are no longer being printed. Supply can only go down from here, so expect to see shock lands steadily rise over the coming months and years. As they are often not four-ofs and are not played in Legacy, shocks are unlikely to see as much of a spike as the Zendikar fetch lands did a couple years ago. On the other hand, fetches are good in Modern precisely because of shock lands, so I expect to see their prices converging, even if fetch lands will remain higher due to Legacy and Vintage demand.

One thing is for sure: if you have any shock lands you're looking to acquire—be it for collecting, playing, investing, or all three—now is the time to pick them up. The next reprint could be years away, and the shock lands won't be getting any cheaper until then.