Ixalan

• Sun Empire

• Brazen Coalition

• River Heralds

• Church of Dusk

Ixalan is an adventure-themed set emphasizing exploration. The plane is home to four primary tribes, each with distinct synergies and advantages that draw off of one another.

• Dinosaurs (green, white, and red): A new creature subtype representing the large reptilian species dominating the plane, with themes including cost reduction and haste thanks to cards like Regisaur Alpha. The set also introduced errata to several older Magic cards with similar creature subtypes, such as Raptor, to become Dinosaurs retroactively.

• Pirates (black, red, and blue): Swashbuckling sailors and fighters who work well in tandem, often focused on aggression as seen on Fathom Fleet Captain.

• Merfolk (blue and green) utilize trickery and deceit to overcome their adversaries, excelling with protection like that of Kopala, Warden of Waves. Merfolk also have a +1/+1 counter subtheme, with many merfolk or merfolk-oriented spells interacting with +1/+1 counters, such as Herald of Secret Streams.[3]

• Vampires (black and white): a bloodthirsty species that drains life incrementally and swarms the board with small creatures, taking advantage of bonuses like that of Sanctum Seeker.

Ixalan included the following mechanics, a mix of new and returning keywords:

• Enrage: An ability exclusive to dinosaur creatures that triggers when they are dealt damage, such as Ripjaw Raptor.
• Raid: A returning mechanic from Khans of Tarkir block that checks if a creature has attacked this turn, providing various bonuses like the Raid ability on Ruin Raider.
• Explore: An ability appearing on creatures. To explore, a player reveals the top card of his or her library; if it is a land, it is put into their hand, and if it is nonland, the creature gets a +1/+1 counter and the player may choose whether to leave it there or put it into the graveyard, as seen on Merfolk Branchwalker.
• Treasure: A new artifact token that can be tapped and sacrificed to produce one mana of any color, produced by several cards such as Revel in Riches. Treasure tokens are similar to the Etherium Cells created by Tezzeret the Schemer, Gold tokens created by Gild, and the Tempest card Lotus Petal.
• Vehicles: A returning artifact subtype. Vehicles have "Crew X," which allows players to tap any number of untapped creatures with total power X or greater to turn the Vehicle into an artifact creature until end of turn, such as Dusk Legion Dreadnought.
• Transform: A returning mechanic involving double-faced cards, appearing on both enchantments and artifacts, which transform into special lands when specific conditions are met, such as Treasure Map. The transform cards are designed to show a quest for a fantastic location, and the lands on the back half are significantly more powerful than regular lands. [4]

All of the above mechanics also appeared in Rivals of Ixalan, with the addition of one new keyword:

• Ascend: A reminder keyword that provides a bonus if players have the "city's blessing". Players obtain the city's blessing by amassing ten permanents on the board in a game, then retain the city's blessing for the remainder of the game, providing bonuses like that of Kumena's Awakening.