Khans of Tarkir is a Magic: The Gathering block consisting of Khans of Tarkir (September 26, 2014), Fate Reforged (January 23, 2015), and Dragons of Tarkir (March 27, 2015). The block's setting is based on a mix of cultures of Central and East Asia. It is the last block to have three expansion sets.
The plane of Tarkir was once dominated by dragons, but in a massive war over a thousand years ago, humans succeeded at wiping them out. Today Tarkir is a battle-torn realm where five clans feud for supremacy. As presented in Khans of Tarkir, the five clans focus on "wedges", or sets of three colors that are rooted in two colors and one "enemy" color across from it. Each wedge is the colors of a clan of warriors that venerate a certain quality of the dragon, and an anatomical feature that represents it. The clans also make use of the "Morph" mechanic, returning from the Onslaught block, which allows creatures to be cast face-down as 2/2 creatures and turned right-side up for additional cost, and occasionally additional benefit; this magic is described as being an invention of the extinct dragons, now adapted to human needs. The clans, and their khans, are as follows:
The Abzan Houses (White/Black/Green) see endurance as the most important quality of the dragon, and use the scale to show that. Their mechanic is "Outlast," which allows them to permanently strengthen themselves by tapping. In Khans of Tarkir, the clan is led by Anafenza.
The Jeskai Way (Blue/Red/White) prefer the cunning nature of the dragon, and represent themselves with the eye. In Khans of Tarkir, the clan is led by Narset. Their mechanic is "Prowess," which gives creatures temporary bonuses every time the player casts a non-creature spell.
The Sultai Brood (Black/Green/Blue) make themselves ruthless like the dragon, and see the fang as its most ruthless part. Their mechanic is "Delve," which allows the player to lessen the mana costs of spells by exiling cards from the graveyard. They are led by Sidisi.
The Mardu Horde (Red/White/Black) views speed as the greatest aspect, and use the wings to represent that. Their mechanic is "Raid," which provides bonuses if the player attacked this turn. In Khans of Tarkir, the clan is led by Zurgo Helmsmasher.
The Temur Frontier (Green/Blue/Red) believe in the dragon's savagery, and use the claw as their symbol. Their mechanic is "Ferocious," which provides bonuses if the player controls a creature with 4 power or greater. In Khans of Tarkir, the clan is led by Surrak Dragonclaw.
Tarkir is the birthplace of the dragon-worshipping planeswalker Sarkhan Vol, first introduced in Shards of Alara. At the beginning of the Khans set, Sarkhan returns to Tarkir and learns that the extinction of Tarkir's dragons was linked to one specific event. Some thousand years ago, there was an epic battle between two dragon planeswalkers: Nicol Bolas, one of the greatest manipulators in the multiverse, and Ugin the Spirit Dragon, who helped trap the Eldrazi on Zendikar. Sarkhan resolves to travel back in time and alter Tarkir's fate. His travels in the Tarkir of 1,280 years ago are chronicled in the set Fate Reforged. He finds a world where the five human clans do not fight each other, instead fending off constant attacks from Tarkir's many dragons; the clans still model themselves on a particular quality, which is epitomized by a Legendary Dragon creature whom each clan reveres and strives to emulate. The set focuses more on the color at the center of each wedge and its ally, with the enemy color given very little presence. The dragons who serve as the inspiration for each clan have their own watermarks, which are modified versions of the clan sigil. Additionally, Morph is missing; instead, a mechanic which is described as being Morph's precursor, "Manifest," allows players to put any card face-down as a 2/2 creature, and flip them again only if their obverse was creatures to begin with.
The Abzan Houses (White, Green, Black) are led by Daghatar and revere Dromoka, the Eternal. In the past, their mechanic is "Bolster," which lets players strengthen the weakest of their creatures.
The Jeskai Way (Blue, White, Red) are led by Shu Yun and revere Ojutai, Soul of Winter. They retain the Prowess mechanic.
The Sultai Brood (Black, Blue, Green) are led by Tasigur and revere Silumgar, the Drifting Death. They retain the Delve mechanic.
The Mardu Horde (Red, Black, White) are led by Alesha and revere Kolaghan, the Storm's Fury. In the past, their mechanic is "Dash," which allows players to cast creatures at reduced mana cost, but with the added corollary that the creature returns to hand at the end of the turn.
The Temur Frontier (Green, Red, Blue) are led by Yasova Dragonclaw (all Temur khans take the title "Dragonclaw") and revere Atarka, World Render. They retain the Ferocious mechanic.
Sarkhan Vol is successful at preventing Ugin's death, though Ugin is forced to retreat into a hibernative state to recuperate. Satisfied, Sarkhan travels back into the "present day." But the Tarkir he finds, as chronicled in Dragons of Tarkir, is drastically changed. The eponymous dragons, no longer extinct, have proliferated, and are now on the verge of wiping out all other life; in particular, the five god-dragons worshiped by the clans are now the leaders of those clans, with the human (or humanoid) characters who led them in the original timeline serving in other roles. In this new future, each of the clans focuses on allied pairs, with the enemy colors of the original wedges abandoned entirely; likewise, each clan retains the modified watermark of their dragonlords, first introduced in the previous set. Morph returns as "Megamorph"; the two mechanics are identical except that creatures with Megamorph gain a +1/+1 counter when flipped. Dragons also creates the peculiar structure of Tarkir Block drafts: Fate Reforged is designed to be drafted with either Dragons or Khans, but the two large sets, representing alternate timelines, are not intended to be drafted together. To that end, Dragons retains the two altered clan mechanics from FRF and replaces the three that remained.
The Dromoka Brood (Green/White) is what the Abzan Houses have become. Dragonlord Dromoka now leads and they retain the Bolster mechanic from Fate Reforged. Anafenza, no longer their leader, was martyred for apostatic religious beliefs, but lives on as a ghost associated with a spirit tree.
The Ojutai Brood (Blue/White) is what the Jeskai Way have become. Dragonlord Ojutai now leads and their mechanic, new to the Tarkir block but returning from Rise of the Eldrazi, is "Rebound," which lets spells re-occur at the beginning of the player's next turn. Narset, their former leader, has ignited her planeswalker spark, and is one of the two planeswalkers in the set (the other being an alternate version of Sarkhan Vol).
The Silumgar Brood (Blue/Black) is what the Sultai Brood have become. Dragonlord Silumgar now leads and their mechanic is "Exploit." When a creature with Exploit enters the battlefield, the player may sacrifice a pre-existing creature to gain extra benefits from the Exploiting creature. Their former leader, Sidisi, exists as an undead thrall to Silumgar.
The Kolaghan Brood (Red/Black) is what the Mardu Horde have become. Dragonlord Kolaghan now leads and they retain the Dash mechanic from Fate Reforged. Their former leader, Zurgo, has been reduced to a mere ceremonial bellringer.
The Atarka Brood (Green/Red) is what the Temur Frontier have become. Dragonlord Atarka now leads and their mechanic is "Formidable," which provides bonuses if the controlling player has creatures whose total power is 8 or higher. Surrak, their former leader, serves as the brood's Hunt Caller.
Khans of Tarkir features a number of new mechanics as well as two returning mechanics (Morph and Delve):
Prowess - An ability that gives the creature +1/+1 until end of turn when non-creature spells are cast by their controller. This is the Jeskai mechanic.
Raid - An ability that activates if a creature is summoned after creatures attack in a player's second main phase. This is the Mardu mechanic.
Outlast - Allows players to place counters on creatures as a sorcery. This is the Abzan mechanic.
Ferocious - Allows players to do different effects when they control a creature with power 4 or greater. This is the Temur mechanic.
Delve - Allows players to exile cards from the graveyard to reduce casting cost, similar to how the Convoke ability uses tapped creatures. This is the Sultai mechanic.
Morph - Allows players to disguise the identities of their creatures by casting them face-down on the battlefield as a 2/2 colorless creature, which can be flipped up at any time by paying its morph cost. All clans can have this mechanic.
Fate Reforged features three new mechanics, with Prowess, Ferocious, and Delve returning from Khans of Tarkir.
Bolster - An ability where players choose the creature with the least toughness that they control, and put +1/+1 counters on it for the Bolster number. This is the new Abzan mechanic.
Dash - An ability where you may cast a spell for its Dash cost. If you do, it gains haste, and is returned to its owner's hand at the beginning of the next end step. This is the new Mardu mechanic.
Manifest - Take the top card of your library and place it face down as a 2/2 colorless creature. If it's a creature card, you may pay its mana cost to turn it face up. All clans can have this mechanic.
Dragons of Tarkir features four new mechanics, with Bolster and Dash returning from Fate Reforged.
Rebound - An ability to cast an additional copy of a spell during your next upkeep. This is the new Jeskai mechanic.
Megamorph - An ability to have creatures who morph unmorph with an extra +1/+1 counter. All clans have this mechanic.
Formidable - An ability that allows you to do something if the total of power among creatures you control is 8 or greater. This is the new Temur ability.
Exploit - An ability that grants you an additional bonus if you sacrifice a creature upon a card with Exploit entering the battlefield.
According to Mark Rosewater, "There is something that people have been asking us to do for quite a while that we’re finally bringing back after a long absence in Magic, and there’s something that people have been asking us to do that we have never done that for the first time we’re doing in Khans of Tarkir", meaning the return of the keyword "morph" and creating a set themed around wedges, respectively. In addition, allied "fetchlands" were reprinted, after originally being seen in Onslaught.
In addition, Wizards of the Coast will be debuting a new two-set block system following the conclusion of Khans, making this the last one to have the traditional three-set system.