Remand: One of the best tempo spells in modern, remand is great against cards that are 2 cmc or greater, and in many situations, remand can act like a Time Walk and make your opponent waste their entire turn. However it feels bad to play this against decks like Elves and Affinity. Ususally 2-4 are run in the main if at all.
Mana Leak: The knock-off Counterspell is great in the early game, but loses value in the late game, usually 2-4 are run in the main.
Rune Snag
: Similarly to Mana Leak, this card is great in the early game, but unlike leak, Snag rewards you for playing more than one, as snag's "stack" effect makes it far superior in the mid-late game.
Logic Knot: Another knock-off Counterspell. Knot is great if your graveyard is full, but when it's not it can be difficult to work, this usually is during the late game.
Negate: This control staple is great against decks like Tron and Scapeshift, and is starting to see maindeck play.
Condescend: This card is sometimes run as a mana leak with an upside, otherwise it's too mana intensive.
Blessed Alliance: A newer option that can get around hexproof and regeneration. This card is flexible enough for maindeck play, quickly finding itself the second-choice removal after path to exile.
Valorous Stance Flexible card that can also protect your own threats. The role this card fills is not generally valued, and it therefore sees little play.
Azorius Charm: Flexible but only temporary answer. Combined with targeting restrictions, this card sees little play. Still, some find the flexible valuable and play 1-2.
Journey to Nowhere: Abrupt Decay makes this card a bit unreliable. However, it is faster than Detention sphere - if more narrow. Often played over path is budget builds.
Declaration in Stone: A budget removal spell that can kill lots of tokens, but it's big downside is that that the clue tokens you give your opponent can definetly add up, so I'm unsure if I would play it over something like Ratchet Bomb.
Wall of Omens: Perfect way to stonewall cards like Wild Nacatl. When combined with Restoration Angel or
Ojutai's Command
, the card advantage can really add up. 3-4 find their way into many builds.
Jace, Vryn's Prodigy
: Slowish addition to the deck, might be too slow/low impact. Still, the card advantage offered is tempting many players into including 2-3 in their maindecks. It helps that
Ojutai's Command
can bring him back into play.
Think Twice
: Card advantage with upside against discard. This source of card advantage is very mana intensive, but can be spread across multiple turns. Many decks opt to play 2-4.
Anticipate: Card selection at instant speed. Again not consistently played, usually 2-3 when it appears.
Secure the Wastes: Moderate efficiency at instant speed to go wide. A new tool that improves the flash game of the deck that works with Snapcaster Mage.
Snapcaster Mage: Amazing card. Works with more spell heavy builds. This card is so good that we should always be looking to play as many as possible. Snap + cryptic is incredibly strong. 2-4 in the maindeck.
Phantasmal Image: Flexible card with varied application. A bit vulnerable, but also very efficient. Not seen often, but 1-2 appear in some lists.
Thing in the Ice
: Cheap threat that might not control the board well enough for the expenditure of tempo on-curve.
Celestial Flare: Strictly worse than Blessed Alliance
Celestial Purge: Mainly used as an answer to Liliana of the Veil, Keranos, God of Storms, Nahiri, the Harbinger, Prized Amalgam, Bloodghast and Blood Moon, this card is flexible enough to frequent sideboards. 1-2.
Disdainful Stroke: Big mana can be an issue, and this is a straightforward answer that sees only fringe play.
Disenchant: Easy sideboard tech with high variance, very worthwhile thanks to snapcaster.
Ethersworn Canonist: Tool against some combo decks, it is not a tool often kept at the ready. 1-2
Kor Firewalker: Watch out for Skullcrack when blocking, but otherwise is the perfect answer to burn. 2-4 depending on how much burn is seeing play.
Meddling Mage
: In the matchups where sweepers are less important, mage can turn off key cards from the opponent. 2-3 can see play if less aggressive metas.
Rest in Peace: Turns off your snapcasters, ojutai's command and finks, but against dredge in particular it can be a knock-out. Usually run as a 1-2 of if at all.
Runed Halo: Answers random combo like
Lightning Storm
or problematic permanents such as Slippery Bogle.
Shadow of a Doubt: Answers Scapeshift, Chord of Calling, Expedition Map and fetchlands while cantripping. Excellent out of the board but you'll never want more than 2.
Spellskite: Another anti-aggro card that infect, affinity, burn and bogles all hate to see.
Spreading Seas: Great option to shut down non-basic lands. This card is good enough to see maindeck play if the meta is warped around powerful lands.
Stony Silence: Affinity, and to a lesser extent, Lantern control and Tron have a hard time playing through this card. Always include at least 1, and let the concentration of affinity in the meta dictate if you need 2 or even 3.
Sword of the Meek & Thopter Foundry: This unban had little effect as the combo isn't particularly quick to assemble, and still takes several turns to win the game. This remains an option, yet only some esper/gifts player have seen even moderate success with it.