Dusk Urchins

Whenever Dusk Urchins attacks or blocks, put a -1/-1 counter on it.
When Dusk Urchins dies, draw a card for each -1/-1 counter on it.

Swamp

Harnfel, Horn of Bounty

Discard a card: Exile the top two cards of your library. You may play those cards this turn.

Birgi, God of Storytelling

Whenever you cast a spell, add {R}. Until end of turn, you don't lose this mana as steps and phases end.
Creatures you control can boast twice during each of your turns rather than once.

Birgi, God of Storytelling // Harnfel, Horn of Bounty

Sol Ring

Trailblazer's Boots

Equipped creature has nonbasic landwalk. (It can't be blocked as long as defending player controls a nonbasic land.)
Equip {2}

Jeweled Bird

Remove Jeweled Bird from your deck before playing if you're not playing for ante.
{T}: Ante Jeweled Bird. If you do, put all other cards you own from the ante into your graveyard, then draw a card.

Hagi Mob

Boast — {1}{R}: Hagi Mob deals 1 damage to any target. (Activate only if this creature attacked this turn and only once each turn.)

Tuskeri Firewalker

Boast — {1}: Exile the top card of your library. You may play that card this turn. (Activate only if this creature attacked this turn and only once each turn.)

Duskwielder

Boast — {1}: Target opponent loses 1 life and you gain 1 life. (Activate only if this creature attacked this turn and only once each turn.)

Behind the Scenes

Creatures you control have skulk. (They can't be blocked by creatures with greater power.)
{4}{W}: Creatures you control get +1/+1 until end of turn.

Draugr Recruiter

Boast — {3}{B}: Return target creature card from your graveyard to your hand. (Activate only if this creature attacked this turn and only once each turn.)

Hot Soup

Equipped creature can't be blocked.
Whenever equipped creature is dealt damage, destroy it.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Jegantha, the Wellspring

Companion — No card in your starting deck has more than one of the same mana symbol in its mana cost. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
{T}: Add {W}{U}{B}{R}{G}. This mana can't be spent to pay generic mana costs.

Rakdos Carnarium

Rakdos Carnarium enters tapped.
When Rakdos Carnarium enters, return a land you control to its owner's hand.
{T}: Add {B}{R}.

Bloodfell Caves

Bloodfell Caves enters tapped.
When Bloodfell Caves enters, you gain 1 life.
{T}: Add {B} or {R}.

Soratami Cloud Chariot

{2}: Target creature you control gains flying until end of turn.
{2}: Prevent all combat damage that would be dealt to and dealt by target creature you control this turn.

Contract from Below

Remove Contract from Below from your deck before playing if you're not playing for ante.
Discard your hand, ante the top card of your library, then draw seven cards.

Mountain

Dwarven Vigilantes

Whenever Dwarven Vigilantes attacks and isn't blocked, you may have it deal damage equal to its power to target creature. If you do, Dwarven Vigilantes assigns no combat damage this turn.

Will-o'-the-Wisp

Flying (This creature can't be blocked except by creatures with flying or reach.)
{B}: Regenerate Will-o'-the-Wisp. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Infectious Horror

Whenever Infectious Horror attacks, each opponent loses 2 life.

Maze of Ith

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Raven Wings

Equipped creature gets +1/+0, has flying, and is a Bird in addition to its other types.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)