Summary
Delve is one of those greatMagic: The Gatheringabilities that can quickly spiral out of control if put on the wrong card, and in some cases, the right cards. This graveyard-based mechanic has since found its way to a handful of cards, some better than others.
Primarily sticking to blue, black, and green cards, plus one red outlier, these can slot into a wide variety of situations and decks, generally with very little setup needed to play them other than getting past a few turns and casting a healthy number of spells. If you’re looking for some versatile spells to include in your next deck, you can’t go wrong with these.

10Murderous Cut
Chop Chop
Instant speed removal is great in any format, and a one mana spell that can take out any creature is even better, though Murderous Cut does have a small stipulation: it costs six mana.
you’re able to get that cost down a bit with exiling a few cards from your graveyard thanks to Murderous Cut’s delve ability. You only need to exile four cards to drop the cost down to just one black mana, which is pretty easy to get to with a healthy mix of cantrips and fetch lands.

9Logic Knot
All Twisted Up
A counterspell that scales with you depending on your needs, Logic Knot is a two mana spell with X in the casting cost, which is where you can use delve to help pay for the cost.
You get to counter a spell with Logic Knot unless an opponent pays X mana. You can scale how much mana you want to dump into it, or how many cards you want to exile, depending on your opponent’s open mana. So if they give five open mana, you can just exile six cards to make sure your opponent won’t be able to resolve their spell.

8Temporal Trespass
Let’s Do The Time Warp
One of the more budget spells that lets you take another turn, Temporal Trespass, has a few things working against it, but that doesn’t mean it’s not a great spell. This normally 11-mana spell lets you take an extra turn, though you have to exile it from the game as it resolves.
That said, you do have the potential to cast this spell for as cheap as just three blue mana, which is cheaper than most extra turn spells, and those generally have a downside. Sure, you have to have eight cards in the graveyard to do it, but it’s still a fine card

7Afterlife From The Loam
Can’t Stay Down
From the Tarkir: Dragonstorm Sultai Arisen preconstructed Commander deck comes Afterlife from the Loam,a reanimator spell that lets you bring backa wide range of creatures all at once. Normally running eight mana, Afterlife from the Loam can reduce its cost with its delve ability.
Afterlife from the Loam lets you pick one creature from each player’s graveyard and bring it back to the battlefield under your control. This spell is only as good as your opponents (and your) best creatures in the graveyard, so give it some time before casting to make sure everyone has something worth stealing.

6Dig Through Time
Only Time Will Tell
A fantastic spell to dig through a good portion of your deck, Dig Through Time lets you take a peek at the top seven cards of your deck. You can then take two of those cards and add them to your hand, not drawing, which is important in case you’re looking to get around draw triggers.
While eight mana is a lot, you can cut it down to just two blue mana with the delve ability, making it much more manageable, especially earlier in a game. Since it’s at instant speed, you can use Dig Through Time on your opponent’s end step to set yourself up at the start of your next turn.

5Sorcerous Squall
A Storm Like No Other
A massive spell that can swing a game in your favor, Sorcerous Squall has you milling an opponent of your choice for nine cards to start. You then get to cast an instant or sorcery spell from that player’s graveyard for free, exiling that spell forever.
Sorcerous Squall costs a staggering nine mana, which becomes much easier to cast since you’re able to exile cards from your graveyard to help pay for the cost with the delve ability. In a deck with lots of other mill effects, you can double the amount of cards your opponent mills, giving you more options for spells to cast.

4Teval, Arbiter Of Virtue
Share The Delve
If you’re not content with having just a few spells that can delve, why not give all your spells delve instead? With Teval, Arbiter of Virtue, you can do just that, since it grants all your spells delve at the cost of a little life.
Casting any spell, regardless of whether or not you’re augmenting the casting cost with delve or not, forces you to lose life equal to that spell’s mana value. You can recoup a little bit of the life lost with Teval’s lifelink ability, so make sure you don’t dip too low.
3Tasigur, The Golden Fang
Choices, Choices
A great pick forCommander players looking to get into a Sultai list, Tasigur, the Golden Fang is a neat Human Shaman creature that comes with delve tacked on, which has an interesting interaction in Commander.
You can use the delve ability to reduce the cost of Tasigur’s Commander Tax as well, keeping you in the game longer. You can fuel your delve strategies with Tasigur’s ability as well, since you’re always milling at least one card per activation. This lets you keep both your hand and graveyard full and dominate the game.
2Treasure Cruise
Crusin’ For A Brusin’
One of the best draw spells around, Treasure Cruise costs anywhere between eight and one mana, depending on how much you’re willing to exile. With delve, you can cut the cost of Treasure Cruise down to just one blue mana, though you need a fair number of cards in the graveyard to do so.
Getting to at least seven cards in the graveyard isn’t too hard,especially in a spellslinger deck, so drawing those three cards will be easy. If you’re able to copy Treasure Cruise or get other effects from drawing cards, you will have yourself a very efficient draw spell.
1Murktide Regent
A Modern Marvel
One of the best creatures to come out of Modern Horizons 3, Murktide Regent is an absolute powerhouse on the battlefield. Formats like Modern and Legacy are where the Dragon shines, popping up in a number of decks across the formats.
Murktide Regent enters the battlefield with +1/+1 counters on it for each instant and sorcery exiled with its ability, letting you catapult it up from a 3/3 up to an 8/8 at most, though you’ll likely settle around a 5/5 or 6/6. Your Murktide will get bigger the longer you play, too, with it gaining new +1/+1 counters anytime an instant or a sorcery card leaves your graveyard.