With Teval, Arbiter of Virtue coming to a Standard format near you, it's a great time to have a look back at one of original Tarkir block's most divisive mechanics.

A Decent Start

But first, we need to go even further back. Delve was first printed as a keyword on three cards in Future Sight: Tomb Stalker, Death Rattle, and Logic Knot. Tomb Stalker, despite being pretty plain-looking by modern standards, has seen fringe play in many formats over the years. Logic Knot, on the other hand, has a storied his-tory of competitive play. Both of them showed signs of what was to come when the mechanic made its debut as a marquee mechanic in Khans of Tarkir.

Death Rattle, for what it's worth, is just kinda weird, but Time Spiral block was a weird time.

Future Sight was designed to be a look into Magic's future, featuring a swathe of abilities and terms which, at the time, didn't yet exist. Delve was one of the stronger ones, but it wasn't printed on enough cards for it to truly stand out. When we first visited Tarkir some years later, however, Delve was everywhere. It dominated Standard and received multiple bans in eternal formats. Delve is such a powerful mechanic that, for quite a while, a vanilla 5/5 was regularly seen in Pro Tour top eights. Gurmag Angler, baby: the best fish to ever do it.

If you search Scryfall for cards with Delve, about half of them have seen serious competitive play and I'm sure many of the others show up in commander. What is particularly fascinating is how many of the best ones are not even rare. Dig Through Time is great, sure, but have you ever cast a one-mana Treasure Cruise? It's banned in multiple formats, so I wouldn't be surprised if the answer is no.

Straightforward Power

Despite its inherent power level, the mechanic is extremely simple. Got dead stuff in your graveyard? You can exile it to reduce the cost of your spells with Delve by an amount equal to the number of cards you exile. Specifically, the reminder text on the cards reads "Each card you exile from your graveyard while casting this spell pays for (1). It's similar to Murders At Karlov Manor's Collect Evidence me-chanic in a lot of ways but Delve is arguably more flexible. You can exile any number of cards in order to delve - including zero - where as Collect Evidence always requires at least the number printed on the card.

So why is Delve so good? Well, Magic has a long history of issues with cards that cheat on mana, and Delve is exactly that. Let's look at Treasure Cruise again. At eight mana, it is atrocious. You would never play that card anywhere, but as a sorcery speed Ancestral Recall? Yeah. In formats where fetch lands are legal, such as during Khans' Standard run, filling up the graveyard is trivial, and casting Cruise for one was not just do-able, but commonplace. It requires a bit of set-up, so it's not literally a common version of a power nine card, but the set-up is often just "playing the game."

Look, Magic's lead designer, Mark Rosewater listed Delve as an eight on his Storm Scale. This is an unofficial list of how likely any mechanic is to return in a Standard set. An eight means that Rosewater considers Delve only marginally less problematic than Epic, a mechanic widely regarded as one of the worst of all time.

Too Good to be True

The thing is, Delve played out very well. A lot of players - myself included - love Delve. In fact, its biggest problem is that it played out too well. Cheap removal spells like Murderous Cut are fine, playable, on the strong side even, but formats have had stronger removal spells and been fine. The problem is that every card with Delve is just better than a non-Delve equivalent. You wouldn't play Become Immense for six mana, but it's been a staple of Infect decks since its printing be-cause +6/+6 for 1 mana is incredible.

In the end, Delve is tricky to write about. There are only so many ways you can say that making spells cost way less than they should causes problems. The mechanic has a proven track record of being tough to balance, and it's no surprise that, even on its home plane, it only returns as a footnote on a couple of cards.

While I look forward to trying to make Teval work in Standard, the added cost of losing life may be too successful of a balancing act. If it does, it sort of proves my point in a way: Delve is so hard to balance, that, in an attempt to do so, Wizards had to add an additional cost to counteract the strength of the ability itself. You know a cost reduction mechanic might be too strong when the only way to make it fair is by adding a different cost.