Temur Delver is a deck so close to my heart. It's a deck that I've been working with for a long time. While I enjoy Spell Queller and that style of Jeskai tempo there's nothing quite like attacking with a diverse range of threats with a diverse range of answers much lower on the mana curve.
Below here I'm going to list each card's primary role in the deck, and then why other cards did not make the cut.
Creatures:
Delver of Secrets
: This is the namesake of the deck. The best turn 1 play, it's okay later in the game, but this is the bread and butter of the strategy.
Tarmogoyf: I personally believe that this is the best two-mana creature to pair with Delver of Secrets
. It's just a huge idiot that attacks really well, and defends even better to help win longer games.
Savage Knuckleblade: This poor guy feels like the joke of the whole temur color combination. However, he is super easy to cast on turn three if you're ahead, and just the simple fact that he has so much versatility makes him a wonderful rounded addition to this deck. He is costly on the mana, but with how cheap this deck is longer games make him a valuable asset.
Rhonas the Indomitable: This guy has been on my radar since he was printed. He screams amazing, but that pesky can't attack or block clause. He is 3 mana, but fortunately all of my creatures need just one pumping, or are big enough on their own to get him in the red zone. I have yet to properly test him in any kind of tournament, but he seems really good on paper. Updates to come on whether he's any good or not.
Snapcaster Mage: Well there's Lightning Bolt in this deck, so of course there's old snap in here.
Instants:
Opt: Here's the loaded one. So normally Thought Scour is in this slot, but Opt offers significantly better card selection. I will go into this part more when I discuss cards that aren't in the deck. But simply, this card makes 1 mana hands keepable, and allows me to effectively use my mana when I don't use it on my various counterspells.
Mana Leak: Speaking of counterspells, Mana Leak is my catch-all. It's job is to disrupt my opponent. This is often saved for my opponent's threats and less for protecting mine when options are available. But it's more often than not just a Counterspell.
Remand: My personal favorite piece of disruption. Remanding a Death's Shadow or a Goblin Guide is the worst, but hopefully that never needs to happen. This is best when you're on the play and after a turn-1 Delver of Secrets
you can Time Walk your opponent.
Spell Pierce: Again a loaded one. This is normally Stubborn Denial, but I feel with the current setup that this being a turn-2 play reliably is huge. Also, nothing feels better than casting Spell Pierce on a Mox Opal turn 1.
Tarfire: This is sort of Lightning Bolt number 5. But it brings an extra card type for goyf which makes it playable.
Become Immense: This is a silver-bullet to win a game out of nowhere when your opponent isn't aware of your hand. One green for this pump spell, and a bolt or two is 12+ damage for 3 mana.
Simic Charm: Same thought with become immense with just a lot more utility. Sometimes it wins a game without your opponent expecting it. Or it bounces something to clear the way for your attackers. Or maybe it blanks a turn of removal spells from your opponent.
Lightning Bolt: Well there's Snapcaster Mage in this deck, so of course there's old bolt in here.
Sorceries:
Serum Visions: One of the best flips for Delver, it gives very little information to the opponent, and smooths out our draws. If all goes well, this card prevents blind top-decking for the first couple turns to gain the advantage.
Forked Bolt: This is actually a flex slot. Roast can also go here. In my local meta there's plenty of affinity, merfolk, burn, and mana dork filled decks running around.
Entrancing Melody: This is the siracha of the deck. Where Threads of Disloyalty fails, this card shines. Occasionally it is just a dead card when you have no mana, but it's the definition of a silver-bullet. Sometimes it will just auto-win the game.
Planeswalkers:
Chandra, Torch of Defiance: This is a weird one. So this deck doesn't necessarily run out of gas, but stalls out. There's a clear ceiling to the deck's potential, but Chandra helps push an even game in your favor. That and sometimes getting that extra card type in the yard for goyf helps.
Artifacts:
Mishra's Bauble: is technically cantrip 9 and 10. This one does not flip delver itself, but combos nicely to help flip delver. If you play a delver and bauble on turn 1 you can crack the bauble on your turn, and look at your deck. If it's an instant or sorcery than you put the draw from bauble on the stack first and let delver reveal that card to flip. If the card you look at is not, then put the draw trigger on the stack second and you get to draw that card, then get a second shot at flipping your delver.
Sideboard:
As with all sideboards, morph them to be appropriate for the expected meta. Temur has pretty good tools against about every archetype, and there's nothing wrong with making your deck as strong as possible.
Ancient Grudge: The classic anti-artifact for Temur. This is the main answer to specifically affinity. Drawing multiples in a game often lead to a free-win. It's fine against tron to punish their slower draws, but this is mostly for affinity.
Destructive Revelry: This is typically the option when you are up against an Aether Vial, or Blood Moon. It's also a very good generic answer to Merfolk.
Dispel, Negate: Just helps buff up the counter suite to fight spell-based decks.
Engineered Explosives: Lingering Souls is a hard card to beat, so why not have a selective board wipe. This also gets rid of most pesky permanents that often fight to stick around.
Huntmaster of the Fells
, Scavenging Ooze, Thrun, the Last Troll: These are all in one as they all serve the same generic purpose. These either replace your bad threats in some matchups, or help diversify your threats even further to become near impossible to answer.
Izzet Staticaster: Remember, Lingering Souls is a hard card to beat. And this can help gain tons of advantage against mana-dork decks, or any deck like Affinity or Elves.
Pulse of Murasa: Steals victory from the jaws of defeat. The main deck often has a few cards that are simply bad. So this can just become a better grind option, or to turn the corner against any aggressive opponent.
Spreading Seas: Pick this or Blood Moon. I run with only 3 non-red basics so I choose to run Spreading Seas. It has the extra benefit of being pretty good against burn and B/G base decks on top of being the normal solution to big mana decks. It just tends to not auto-win as many games as Blood Moon
Roast: same with the description of Forked Bolt above. Swap these out depending on the metagame. Good against the delve threats, and eldrazi.
Cards that didn't make it:
Thought Scour, Hooting Mandrills: So normally Thought Scour is the default second-cantrip for temur. Hooting Mandrills is a pretty good creature to play on turn 2 or 3. However Savage Knuckleblade often does the same job as the monkey madness. Thus the flaw of Thought Scour is revealed. There's no real card selection with scour. Opt offers significantly greater selection, and allows for a more consistent game to be played. This kind of tempo deck doesn't do well when luck isn't on your side. So if Thought Scour doesn't pan out how you need, the game is often lost. Opt allows the moments of feel-bad to be mitigated through better play.
Bedlam Reveler: I tried to replace some Hooting Mandrills with this card, but it's just not the kind of creature this deck wants to play.
Stubborn Denial: This may still be better here over Spell Pierce, but I keep finding times where having a delver on turn 1, and having a second one on turn 2, with spell pierce to be a very strong play.
Seal of Fire: This is trying to hard to make goyf good. It's plenty fine without this weird card.
Spell Snare: Terminate is not super threatening even though it's common. Fatal Push, Kolaghan's Command, and opposing Lightning Bolt are the cards that need countered. Sure countering an opposing Tarmogoyf is great, but that isn't where counterspells typically need pointed.
Matchups:
So now that the breakdown of the deck is done. This is how I feel the deck performs in specific matchups. My local meta is fairly representative of modern as a format. Not much real off-the-wall stuff, and plenty of variety.
Grixis Death's Shadow: This is a weird one. I think this current build is slightly better in this matchup compared to my previous Temur Delver build. Bolt-snap-bolt is how the matchup often ends, but remanding their turn 2 gurumag angler is so amazing there aren't words for it.
Elves: if you have the removal you can get this one easy. They have very little to stop you from just beating them to death with Delver of Secrets
and Tarmogoyf. Save removal for the important elves, or if you identify a weak hand. Practice it a bunch to find these weak points and it should go in your favor. Do not be afraid to mulligan for a better hand. Elves is very good at punishing a weak start from this deck.
Merfolk: Oh this deck is such a nightmare for me specifically. I think it's a pretty even matchup, but I just can't wrap my head around how this deck ticks so I just don't do well against it.
Jund/Abzan/GB Rock: All of these decks are trying to do roughly the same thing. Fortunately this deck can grind fairly well, and has an okay matchup. Decision making is critical here, and some luck to draw well and steal the game.
Affinity: I have gotten so much practice in here that I feel amazingly confident against it. This deck is fast enough to compete in speed, and has a ton of good answers. Get some reps in against this deck and make sure to keep good hands. Just like Elves, Affinity can punish a bad hand from you.
Tron (not eldrazi): This is a classic example of a big mana deck beating up on a deck that likes card advantage. being on the play is huge, and keeping the fastest hand possible leads to won games. Just try to get them to stumble once or twice and you can get there.
Eldrazi anything: Regardless of the colors, if any, the cards to be afraid of are all the same. Thought-Knot Seer, and Reality Smasher are pretty spooky. Roast is very good here, and having a massive Tarmogoyf helps a lot. Let Delver of Secrets
stretch before the match because he's going to do a lot of carrying.
Burn: The die roll matters here, but so do counterspells. This deck fetches basics well so think carefully about land drops, and play around the idea that your opponent always has the answer. Spreading Seas is a Stone Rain that cantrips here so use this to mess with their early game.
Jeskai Tempo: This kind of goes in their favor. Typically I am the person playing this deck at a local event, but it's pretty common these days so be prepared for it. Spell queller can be a beating if you're not playing around it so make sure to expect it. Geist should be countered if ever possible. Trying to leave a blocker up for it typically never works unless you have a super threat-heavy hand.
Hard Control of any color combination: Be it Azorius, Jeskai, Grixis, or Esper they all tend to have the same type of cards in it. They are increadibly threat-light so if you can deal with the ones they draw you're favored. They typically can't ever establish a "hard lock" and will get run-over if they run out of answers.
Storm: My advice is to always pick up and play storm. You'll learn where it's soft and be able to have one simple counterspell fizzle their going-off. Otherwise keep a fast hand, make sure you always have at least one counter-spell and one bolt in hand to keep them from going off. They can't delay creatures once they're on the battlefield so get them down early and let them sculpt their hand a bit. Hit them where it hurts on Gifts Ungiven or Past in Flames.