I've been so wrapped up in Hour of Devastation previews that I haven't had a chance to cover the pulse of the market for a couple of weeks. Don't worry—I'll do my best to talk about everything that's happening in the world of Magic finance, including a couple of really interesting price spikes.
Hour of Devastation's Solemnity made a bunch of older cards a lot more powerful, and all of the above spells have roughly doubled in value. Decree of Silence might be an eight-mana enchantment, but if you can get it onto the battlefield with Solemnity, your opponent can no longer resolve spells. Mystic Remora and Glacial Chasm have always been pretty powerful, but they're kind of absurd when you no longer have to worry about paying their cumulative upkeep costs.
Phyrexian Soulgorger is a little less powerful, but an 8/8 for three is still well above the curve. Celestial Convergence requires a bit of setup, but a four-mana card that wins you the game by itself is really nice.
These combos seem a bit too cute to me for Legacy or Modern, but Mystic Remora and Glacial Chasm see occasional play in Vintage, so it's certainly possible that Solemnity will find its way into one of those decks. I think Solemnity is going to make a bigger splash in Commander, though, which is why I'm more bullish on the splashy, expensive combo pieces like Decree of Silence than the boring, efficient ones like Phyrexian Soulgorger.
If you believe that Solemnity / Decree of Silence is a tournament-level combo, might I suggest Enduring Ideal as a potential spec target? That card has always been lurking on the fringes of competitive play, and the fact that it was printed in Saviors of Kamigawa means that it wouldn't take much demand for the price to quadruple. It's far from a sure thing, but there's some real upside here.
Elephant Grass is another card that I have my eye on. It's probably not powerful enough to start showing up in Legacy again, but it's a nifty Commander combo with Solemnity that's fairly playable on its own. Elephant Grass just $1 right now, and I wouldn't be shocked if it ends up spiking to $4-$5 at some point over the next couple of weeks.
Standard is in a holding pattern heading into the Hour of Devastation Prerelease. The market is behaving with a heavy dose of skepticism about how good this new Standard format will be as well as how much of an impact Hour of Devastation will have.
This makes sense. The set appears a bit underpowered, summer has always been Magic's slowest season, and the frustrating raft of bannings certainly didn't help instill any confidence in the market. The metagame is actually pretty healthy right now, though, so I do expect that we'll start to see some prices start to slowly creep up as soon as next week.
The Lorwyn version of Thoughtseize was up more than $10 this week, and the Theros version should follow suit before long. It's one of the most important cards in Modern, and demand is far outstripping supply right now. Current retail on the Theros Thoughtseize is $30, and I bet it finishes the year above $40.
Goryo's Vengeance saw a major jump about a week and a half ago, mostly thanks to the spotlight it has been getting on a couple of popular online streams. The card has felt underpriced to me for quite a while now, and I'm mostly just surprised that the spike didn't happen sooner. I wouldn't be surprised if $40-$50 is the new normal for Goryo's Vengeance, and I don't think you'll lose much value by holding these a while longer.
Lands has been putting up solid results in Legacy recently, and there have been some rumblings that Mirage Mirror will give the deck an additional boost. As a result, Drop of Honey saw an absolutely massive spike from under $100 to over $250. I don't think it'll maintain that price tag for long, but the supply on Arabian Nights cards is so low that I bet it'll stay over $150 for quite some time.
That said, I'd rather invest in The Tabernacle at Pendrell Vale. It's still not up to its historical high—the card was worth about $200 more last summer—but recent movement seems to indicate that another market correction might be on the way. If you've been putting off buying one of these for a while, I'd pick it up soon.
There have been a lot of Commander-related spikes recently. The Scorpion God has the casual world buzzing, and there have been a couple of interesting secondary spikes as a result, Necroskitter and Kulrath Knight chief among them. There's a lot of overlap with Hapatra, Vizier of Poisons, but The Scorpion God has a few unique tricks up its sleeve.
I like Everlasting Torment as the next The Scorpion God spike. It was printed in Commander 2016, but that shouldn't be enough of a supply increase to match demand once all The Scorpion God players realize that this is one of the best cards in their new favorite deck. It's currently a $0.99 card, and I bet it'll hit $4-$5 this summer.
Captain Sisay and Reki, the History of Kamigawa both saw crazy spikes about a week ago thanks to the blurry Ixalan leak, which may indicate that planeswalkers will be errata'ed to gain the "legendary" supertype. If that does come to pass, you'll be able to fetch your planeswalkers with Captain Sisay and draw cards when you play them with Reki.
This information is too speculative for me to condone buying these cards, especially post-spike. I'm selling into the current hype, though there will likely be another spike in the fall if all the planeswalkers are given the expected errata.
I have no idea why Season of the Witch saw a major jump in price last week, but it did.
Maybe some local store is planning to give them out at Halloween and bought a bunch of copies in advance? Maybe someone thought that it would combo with Solemnity? Maybe it sees play in some Legacy deck that I can't find anywhere? I suspect it was just another semi-random Reserved List buyout, but I'm keeping an eye on Peacekeeper just in case. That's a Reserved List card that plays pretty well with Season of the Witch, so if this thing does show up somewhere, Peacekeeper might make an appearance as well.
The last casual spike I want to talk about is Mana Echoes, which jumped from just over $10 to more than $20 about a week ago. It's a neat Commander combo with The Scarab God, and it's only going to get better once the fall brings us a bunch of new casual tribal goodies. My only problem with Mana Echoes? It's primed for a reprint, and it'll end up at $2 when that happens. I'm selling into the current hype just in case.
If you're looking for the next tribal card to spike, take a gander at Patriarch's Bidding.
It's been creeping up in price for months and seems primed to end up at $30 before long. If you need a copy, get it ASAP.
There was another leak this week: the "Feline Ferocity" deck from Commander 2017. Hooray for Cat tribal! Amonkhet gave us a bunch of good kitties, and I expect the foil copies of those to end up gaining value between now and when that deck hits shelves. If you're a Commander speculator, get in ASAP.
Beyond that, buying older cards is risky. If you buy a bunch of casual Cats that end up being reprinted in the deck, you won't be able to move them at all. If you buy a bunch of casual Cats that end up not being included, they might end up surging in price. How lucky do you feel?
When it doubt, focus on foils and remember that this Preconstructed deck will likely not have a Kemba-esque focus on equipment. Jedit Ojanen of Efrava, Qasali Pridemage, Leonin Arbiter, Leonin Relic-Warder, Fleecemane Lion, and White Sun's Zenith seem like interesting choices. Brimaz, King of Oreskos is riskier, but with more upside. I like Jazal Goldmane best, since it's the least likely to be reprinted in this set.