Runed Halo ?

for land, Cavern of Souls is very useful as well, and I even know some who like things like Ghost Quarter in the SB. if you are running a non-activated ability based deck, Suppression Field is fantastic. Kataki, War's Wage is pretty boss for artifact removal. Counterspells like Spell Pierce and/or Condescend are strong too. Timely Reinforcements is a great sideboard card, and all the Ravnica charms save Gruul Charm , and maybe Dimir Charm are super strong as well.

Suppression Field sees play in white decks as a way to hinder Twin decks without repeatedly having to hold up mana, also is pretty hard for most Twin decks to remove. Also is pretty reasonable against Affinity.

Batterskull is used in a lot of tempo decks out of the board against slower decks to provide a stronger late game (Twin, UR Delver, things like that).

I've heard talk of Boom/Bust out of the board for tempo decks to attack mana bases, I don't know how I feel about the symmetry though.

grrr ... tough choice awesomeguy37.

The only thing that card does that Leyline of Sanctity doesn't is protect me from damage. So lets say against a control match-up, I'd block a man-land/Snapcaster Mage /Vendilion Clique . Against tron or a green ramp deck I'd block one of their more used power creatures. It could be used against Splinter Twin to hose their combo creatures.

So I guess it is an add on.

Suppression Field , Batterskull , Ghost Quarter , Kataki, War's Wage and Cavern of Souls will all get additions, though if you are going to mention counterspells, can you be specific? There are many.

Also, TheHorse and GoofyFoot, you'll have to make better arguments for Boom/Bust and Timely Reinforcements .

Illness in the Ranks - 1 mana enchantment that says 'fuck you twin' and can deal damage to BW tokens but isn't as successful due to things like Intangible Virtue . Certainly slows tokens down though.

Added ChiefBell

Fracturing Gust Eidolon of Rhetoric Threads of Disloyalty Gaddock Teeg

Rule of Law for the storm matchup.

Not sure if Rapid Hybridization should be included, I'm only including it because Blue usually has problems taking care of things permanently.

Hurricane or Arashi, the Sky Asunder should be included as Green's middle finger to flying creatures.

Ethersworn Canonist , Eidolon of Rhetoric and Wear / Tear

Obstinate Baloth , Thrun, the Last Troll , Slaughter Pact .

You know, Jund has a sideboard too... Lol.

Also, Thalia, Guardian of Thraben , Lodestone Golem , Trinisphere , basically anything in Hate Bears.

Obstinate Baloth , Thrun, the Last Troll , Slaughter Pact , Thalia, Guardian of Thraben , Lodestone Golem , Trinisphere , Ethersworn Canonist , Eidolon of Rhetoric , Threads of Disloyalty , Gaddock Teeg and Rule of Law will all get submissions.

DaShPrime and masta_biomanca; You will have to make better arguments for Fracturing Gust , Rapid Hybridization , Hurricane and Arashi, the Sky Asunder .

I already had Thrun, the Last Troll and Wear / Tear in there. Oh well.

Timely reinforcements sees tier on sideboard play occasionally?

Give an example GoofyFoot, provide decklists, dictate which decks it should be used with/against. I've never seen it used once through OCTGN, untap.in or even here on T/O.

Dispel , Spell Pierce , Negate , Counterflux and a couple of other counterspells see sideboard play to bring in against controlling decks, especially out of the sideboards of fragile aggro and combo decks.

Also, Spellskite should be a four-of. :)

You forgot Shatterstorm also Twisted Image is seeing SB play in a lot of tempo decks as a way to help deal with Deceiver Exarch Spellskite etc. As far as counter spells go Spell Pierce , Spell Snare , Counterflux , and Swan Song are all commonly found in side boards. I feel the reason for each is self evident but if you want me to explain I can. Lastly, Spreading Seas is found in fish decks and used in others as a kind of land destruction.

P.S. You also forgot Flame Slash

@ thispersonisagenius and HardcorePawn:

I'll add Shatterstorm , Spell Pierce , Spell Snare and Counterflux . As for the cards I didn't include, don't see Negate all to often, as it is a limited counter. Swan Song is also limited, and kinda dangerous with that 2/2 flying token. While not very relevant in vintage or legacy that might use Swan Song , that bird token is more potent and dangerous in modern. Dispel , same issue, limited use. Twisted Image isn't very good, as it relies on another card to provide damage to the combo pieces, and rarely is a Spellskite hate card ever needed. Spreading Seas is a bit too limited in what uses it so not really a staple, and Flame Slash is only really used by Jund. I could be wrong on the Flame Slash thing though.

I'll be cleaning out this deck though, I need to remove redundancies (especially in white) with all the cards that do the same thing.

Negate does see minimal play, but lots of Twin decks side it in so I might include it just for posterity.

Swan Song regularly comes out of combo sideboards to deal with Twin and opposing counterspells, and you'd be amazed how little the 2/2 matters. Dispel is the same deal, and is very strong against pretty much very blue deck and control decks and combo decks alike side it in.

Twisted Image even sees maindeck play nowadays. Twin, Pod and occasionally other decks maindeck Spellskite , and otherwise it kills Affinity creatures and mana creatures. Again, you'd be surprised how common Spellskite is and how it demands an answer a lot of the time.

Flame Slash sees regular maindeck play in Twin decks to deal with Spellskite .

Conclusion: Spellskite should be a four-of.

Fracturing Gust has seen play in green and white decks as a top-end affinity/enchantment sweeper. Since it sweeps both types, I've seen it in both control lists and green ramp lists to take care of robot decks primarily, with the added bonus against hexproof bogles and enchantment control decks. It's definately worth the inclusion in this list of modern SB cards.

Also Twisted Image doesn't look good on paper by itself, but right now in the current modern meta many decks that have access to blue are using it to destroy Spellskite , Noble Hierarch , Birds of Paradise , and to bring Deceiver Exarch into boltable range. It's used in the SB of most infect decks, some Splinter Twin lists, and a few UWR control lists I've seen as well as all the rogue combo decks that need to take care of a Spellskite before going off. It's a choice that nobody was using a few months ago, but since Pod and Infect lists have been on the upswing it's seeing more play. Spellskite seems to be the MVP SB card in general right now, since Lightning Bolt has been running around as the most efficient removal in modern for a while, so having dedicated Spellskite hate is a natural evolution in modern sideboarding for decks that care about it.

Flame Slash isn't as popular generally, but if you run a non-burn red deck, it's becoming more popular to use than Dismember to avoid the life loss against creature decks. It takes out small goyfs and exarchs out of twin. It's worth the inclusion moreso than some of the cards I see on this list.

Swan Song I've seen in merfolk lists (since the islandwalk in fish as well as all the lords make a lousy 2/2 on the other side irrelevant) as well as pyromancer storm lists (storm uses it as an alternate wincon, countering their own spells to make small armies of 2/2 flyers in case the opponent has a Leyline of Sanctity out or something similar).

Dispel is common in Infect sideboards, and I've seen players use them in my meta in other blue lists as well. I'd include it before Negate however, as I've not seen that played except in budget lists.

I've also seen Molten Rain in non-burn lists nowadays as a cheaper Fulminator Mage , along with its cousins Cryoclasm and Peak Eruption (solely in burn SB's for the 2nd two). The second 2 I wouldn't classify as 'staples' (as to the title of your list here), but I'd add Molten Rain for sure.

Gemini knows his stuff i like this guy.

Thanks for the info people, what do you think of Spreading Seas , GeminiSpartanX?

Are there any cards currently in this list that really have no place?

There are a ton of cards that don't fit on the list. I'll try to find time to look through completely, but as it stands Autumn's Veil , Brave the Elements , Indomitable Archangel are some cards that exactly no one plays.

Spreading Seas seas play in Blue Moon maindecks/sideboards, and sometimes out of UR Twin or Delver. I would put it in. (sea what I did there?)