Eidolon of Rhetoric great card vs Storm, Ad Nauseam and others

Well, for Storm or abzan Vs. Burn you could use Aetherflux Reservoir

Why for Abzan? Abzan doesn't really play more than one spell a turn, and they don't reach 50 life. They'd rather play Siege Rhino or Kitchen Finks. As for storm, that comes down much too late to even get anywhere. Unless someone has better experience with storm I don't think I'll be adding it.

no Slagstorm? :(

I think one card you should consider adding is Patrician's Scorn. It is very similar to Paraselene in that it destroys all enchantments, and while it doesn't get you the lifegain it can usually be cast for free in a deck that wants it, such as white weenie or another deck that has a high number of white spells. Needless to say, this is great against most (if not all) prison strategies.

Prison strategies are actually showing competitive standing WhisperingBlade? If anything, almost all of my enchantment removal stuff should be removed as their entire purpose, Boggles, is never really going to be a prominent deck anymore.

Forgot I had already done most of that a while back.

Hide/Seek destroys combo decks. Ad Nessam, Nihili (-> Emrakul), Storm, etc. Besides, it is useful vs Affinity (among other decks).

Thanks!

what about Hermit of the Natterknolls  ^Flip for any control deck matchup?

it dodges fatal push if they don't have revolt and has 5 toughness once it flips, so it dodges bolts as well

Fragmentize is good

Repeatable removal against x/1s: Liliana, the Last Hope and Izzet Staticaster.

Stubborn Denial and Countersquall are better Negates in some lists.

Nihil Spellbomb can wipe graveyard one sidedly like Tormod's Crypt and it cycles like Relic of Progenitus. Also leaving a mana open is only needed for drawing a card and it can be used just to exile the grave, if needed when tappedout.

Ceremonious Rejection is great against, affinity, eldrazi and tron.

Zealous Persecution, is great in wide strategies against x/1s. It's not as flexible as Golgari Charm, but it does thas one mode better and is on different colours.

Kalitas, Traitor of Ghet fits in some black midrange decks sideboars to fight aggressive decks. Everything that applies to Rhox War Monk applies here and in addition, it stops some graveyard synergies like Kitchen Finks and Voice of Resurgence and 2/2 zombies are quite helpful for blocking.

My last suggestion to the list is Ajani Vengeant. It is good against most of the mid-rangey lists. Keeping manland, Tarmo or DS tapped down is useful, helix is not bad either and one sided Ravages of War wins game.

Great list! Its nice to have a rescource like this. The main thing I would add to this list is alternate wincons. Many control decks side, elspeth sunschapion, keranos, batterskull ect.... also some plainswalkers like JaceAot and GideonAoz see side board play.

What about Guttural Response and Ricochet Trap in red decks to combat counterspells?

Also think Kozilek's Return deserves a spot next to Volcanic Fallout for being more splashable, not hitting your own face, and killing Etched Champion and Master of Waves

Xathrid Necromancer is an extremely good sideboard card for humans which is a top deck right now.

I think it would be helpful if this list included custom categories based on what archetype the sideboard card is meant to be played against. That would probably be alot of work for you, but it would be super handy. :D

Thank you so much! :P

Witchbane Orb?

I am fairly dubious about Cavern of Souls being a sideboard staple, as it is generally run as a playset mainboard.

I believe that Gideon, Ally of Zendikar shows up from time to time in multiple flavors of Death & Taxes. I've also seen Nissa, Steward of Elements in traditional Bant Knightfall lists.

I also have seen Flaying Tendrils used out of Death's Shadow builds as a wrath effect that exiles, so it is effective against the protection of Etched Champion and Mirran Crusader, but it also has the exile effect of Anger of the Gods to hit Kitchen Finks and Dredge decks.

What about mono B control?

Is that an archetype displayed on ModernNexus or MtGTop8, Flooremoji?