Thanks to a production mix-up with Lorwyn Eclipsed prereleases, the TMNT MTG spoiler season has technically started early. Yesterday, Wizards officially revealed every rare and mythic from the set to save players from squinting to decipher leaks. While there’s plenty to enjoy within this 61-card spoiler dump, it seems these cards haven’t stolen the show.
Instead, with its official release drawing ever closer, MTG players are still fixated on Lorwyn Eclipsed. Considering the strength of the set’s two precons, this isn’t surprising at all, as both offer compelling and powerful themes. The Blight Curse deck, in particular, makes a rather oppressive archetype fair game, enabling tons of underutilized synergies.
Since -1/-1 Counters have been unsupported for so long, this has caused a wide range of price spikes. These have been going on since the precons were revealed over two weeks ago, and they’ve not stopped yet. Most recently, Corrosive Mentor has spiked by 389% thanks to its impressive synergy within the Blight Curse deck.
MTG Corrosive Mentor
First printed in 2008’s Shadormoor, Corrosive Mentor is a very simple, but potentially very effective, MTG card. Theoretically playable in any mono-black or black-aligned deck, this card makes blocking significantly more troublesome. Even at three mana, this is theoretically a major boost for many decks, but, realistically, Commander is rarely 100-card piles of generic value.
Thankfully, while synergy is the name of the game, Corrosive Mentor can definitely keep up in this department. Using Commanders like Massacre Girl, Known Killer, it’s possible to build Wither-focused decks that lean on this mechanic. Additionally, this card is a regular feature within -1/-1 Counter-focused decks, like those led by The Scorpion God.
Naturally, the -1/-1 Counter synergy that Corrosive Mentor offers also makes it a perfect fit for the Blight Curse precon. Whether you’re running Auntie Ool, Cursewitch or The Reaper, King No More in the command zone, Corrosive Mentor offers tons of value. As if working well with the Commanders wasn’t good enough, this card is a perfect fit for the precon’s 99.
Out of the box, 21 of the deck’s 28 creatures get Wither from Corrosive Mentor, ensuring you’re always dishing out -1/-1 Counters. This, in turn, amps up many of the deck’s already powerful cards like Dread Tiller, Necroskitter, and Village Pillagers. Thanks to this synergy, it’s little wonder that Corrosive Mentor has seen a significant uptick in demand.
Previously, according to EDHREC, Corrosive Mentor only saw play in around 9,300 decks. Thanks to the new Blight Curse precon, however, this number has been bumped up to roughly 10,200. While this isn’t the biggest increase, it’s nevertheless a lot of new eyes on this otherwise rarely used card.
The Spike
Since Corrosive Mentor has only been printed once, supply for this card has always been fairly limited. The fact that it comes from a poorly received set almost 18 years ago certainly doesn’t help matters, either. Due to these factors, Corrosive Mentor has always held a decent bit of value, typically selling for around $3-4.
Sadly, this low price point is now a distant memory, as prices quickly shot up once Blight Curse was revealed. Once it was confirmed that this card wasn’t being reprinted, over 170 near-mint non-foil copies would be sold in the following weeks. Curiously, as this sales surge started, the price of Corrosive Mentor actually dipped down to $3.52 before climbing properly.
Now, near-mint non-foil copies of Corrosive Mentor are selling for $17.24, including shipping. While the market price figure is still a ways behind this price point, recent copies have even been selling for slightly more. To date, Corrosive Mentor has spiked an impressive 389% in just two weeks.
Thankfully, if this cost feels too dear, it is possible to get a slight saving with a worse-condition copy. Lightly played examples, for instance, are currently going for around $12.50, which even includes shipping. Unfortunately, due to the lack of a reprint, there are very few copies available at this price point, so they may not last long.
Potentially Pricy?
Realistically, when looking ahead, there’s a good chance that Corrosive Mentor will follow the usual pattern for precon-based price spikes. While it’s already shot up a bunch, this card will likely continue to climb in the short term. Since Lorwyn Eclipsed hasn’t officially been released yet, even though it’s playable, demand is unlikely to die out overnight.
Looking further into the future, we can also expect Corrosive Mentor to crash in price once attention shifts away. As interesting as Blight Curse is, we’re bound to get tons of precons throughout 2026 that’ll steal the show. Even if the Teenage Mutant Ninja Turtles set doesn’t manage this, Secrets of Strixhaven certainly should.
While a continued climb before an inevitable fall is predictable, it remains to be seen where Corrosive Mentor will settle. Considering that all of the recently bought copies are unlikely to return to the market, Corrosive Mentor is unlikely to drop back to $3.50. Potentially, Corrosive Mentor could become a $5 MTG card, provided there’s some lingering demand.
Unfortunately, as much as Corrosive Mentor has decent potential in Commander generally, -1/-1 Counters isn’t the most supported archetype. Due to this, there’s a good chance that demand for this card could end up fading sooner than expected. Ultimately, since we can’t predict the future, we’ll just have to wait and see what happens in the coming weeks and months.
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