Realmbreaker's Grasp

Enchant artifact or creature
Enchanted permanent can't attack or block, and its activated abilities can't be activated unless they're mana abilities.

Swordsworn Cavalier

Swordsworn Cavalier has first strike as long as another Knight entered the battlefield under your control this turn.

Tidal Terror

Whenever Tidal Terror attacks, you may tap two other untapped creatures you control. If you do, Tidal Terror can't be blocked this turn.
Islandcycling {2} ({2}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Halo Hopper

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)

Hangar Scrounger

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Whenever this creature becomes tapped, you may discard a card. If you do, draw a card.

Mountain

Island

Knight of the New Coalition

Vigilance
When Knight of the New Coalition enters, create a 2/2 white and blue Knight creature token with vigilance.

Compleated Conjurer

When this creature transforms into Compleated Conjurer, exile the top card of your library. Until the end of your next turn, you may play that card.

Captive Weird

Defender
{3}{R/P}: Transform Captive Weird. Activate only as a sorcery. ({R/P} can be paid with either {R} or 2 life.)

Captive Weird // Compleated Conjurer

Wrenn's Resolve

Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Trailblazing Historian

Haste
{T}: Another target creature gains haste until end of turn.

Sigiled Sentinel

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Vigilance

Tetsuko Umezawa, Fugitive

Creatures you control with power or toughness 1 or less can't be blocked.

Kitesail

Equipped creature gets +1/+0 and has flying.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Kithkin Billyrider

Enduring Bondwarden

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
When this creature dies, put its counters on target creature you control.

Swiftwater Cliffs

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {U} or {R}.

Plains

Preening Champion

Flying
When Preening Champion enters, create a 1/1 blue and red Elemental creature token.

Boon-Bringer Valkyrie

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following abilities until end of turn.)
Flying, first strike, lifelink

Baral and Kari Zev

First strike, menace
Whenever you cast your first instant or sorcery spell each turn, you may cast a spell with lesser mana value that shares a card type with it from your hand without paying its mana cost. If you don't, create First Mate Ragavan, a legendary 2/1 red Monkey Pirate creature token. It gains haste until end of turn.

Burnished Dunestomper

Tarkir Duneshaper

{4}{G/P}: Transform Tarkir Duneshaper. Activate only as a sorcery. ({G/P} can be paid with either {G} or 2 life.)

Tarkir Duneshaper // Burnished Dunestomper

Ephara's Dispersal

This spell costs {2} less to cast if it targets an attacking creature.
Return target creature to its owner's hand. Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)