Harmonic Sliver

All Slivers have "When this permanent enters, destroy target artifact or enchantment."

Torch Song

At the beginning of your upkeep, you may put a verse counter on Torch Song.
{2}{R}, Sacrifice Torch Song: It deals X damage to any target, where X is the number of verse counters on Torch Song.

Boros Guildgate

Boros Guildgate enters tapped.
{T}: Add {R} or {W}.

Golgari Guildgate

Golgari Guildgate enters tapped.
{T}: Add {B} or {G}.

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Deathrender

Equipped creature gets +2/+2.
Whenever equipped creature dies, you may put a creature card from your hand onto the battlefield and attach Deathrender to it.
Equip {2}

Thundersong Trumpeter

{T}: Target creature can't attack or block this turn.

Snow-Covered Mountain

Revelsong Horn

{1}, {T}, Tap an untapped creature you control: Target creature gets +1/+1 until end of turn.

Hymn to Tourach

Target player discards two cards at random.

Threnody Singer

Flash
Flying
When Threnody Singer enters, target creature an opponent controls gets -X/-0 until end of turn, where X is your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Seller of Songbirds

When Seller of Songbirds enters, create a 1/1 white Bird creature token with flying.

Howling Chorus

Creatures with power less than Howling Chorus's power can't block it.
Whenever Howling Chorus deals combat damage to a player, create a 3/2 colorless Eldrazi Horror creature token.

Shrill Howler

Creatures with power less than Shrill Howler's power can't block it.
{5}{G}: Transform Shrill Howler.

Shrill Howler // Howling Chorus

Island

Gruul Guildgate

Gruul Guildgate enters tapped.
{T}: Add {R} or {G}.

Simic Guildgate

Simic Guildgate enters tapped.
{T}: Add {G} or {U}.

Seething Song

Seasinger

When you control no Islands, sacrifice Seasinger.
You may choose not to untap Seasinger during your untap step.
{T}: Gain control of target creature whose controller controls an Island for as long as you control Seasinger and Seasinger remains tapped.

Chorus of the Conclave

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)
As an additional cost to cast creature spells, you may pay any amount of mana. If you do, that creature enters with that many additional +1/+1 counters on it.

Snow-Covered Swamp

Plains

Battle Hymn

Snow-Covered Forest

Hymn of Rebirth

Put target creature card from a graveyard onto the battlefield under your control.

Selesnya Guildgate

Selesnya Guildgate enters tapped.
{T}: Add {G} or {W}.

Rubinia Soulsinger

You may choose not to untap Rubinia Soulsinger during your untap step.
{T}: Gain control of target creature for as long as you control Rubinia and Rubinia remains tapped.

Multani's Harmony

Enchant creature
Enchanted creature has "{T}: Add one mana of any color."

Harmonic Convergence

Put all enchantments on top of their owners' libraries.

Snow-Covered Island

Singing Bell Strike

Enchant creature
When Singing Bell Strike enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.
Enchanted creature has "{6}: Untap this creature."

Siren of the Silent Song

Flying
Inspired — Whenever Siren of the Silent Song becomes untapped, each opponent discards a card, then each opponent mills a card.

Maralen of the Mornsong

Players can't draw cards.
At the beginning of each player's draw step, that player loses 3 life, searches their library for a card, puts it into their hand, then shuffles.

Plaza of Harmony

When Plaza of Harmony enters, if you control two or more Gates, you gain 3 life.
{T}: Add {C}.
{T}: Add one mana of any type that a Gate you control could produce.

Dwarven Song

One or more target creatures become red until end of turn.

Azorius Guildgate

Azorius Guildgate enters tapped.
{T}: Add {W} or {U}.

Song of Freyalise

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Until your next turn, creatures you control gain "{T}: Add one mana of any color."
III — Put a +1/+1 counter on each creature you control. Those creatures gain vigilance, trample, and indestructible until end of turn.

Song of Blood

Mill four cards. Whenever a creature attacks this turn, it gets +1/+0 until end of turn for each creature card put into your graveyard this way.

Render Silent

Counter target spell. Its controller can't cast spells this turn.

Siren Song Lyre

Equipped creature has "{2}, {T}: Tap target creature."
Equip {2}

Entrancing Melody

Gain control of target creature with mana value X.

Atarka, World Render

Flying, trample
Whenever a Dragon you control attacks, it gains double strike until end of turn.

Harmonize

Kolaghan Stormsinger

Haste
Megamorph {R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When Kolaghan Stormsinger is turned face up, target creature gains haste until end of turn.

Disharmony

Cast this spell only during combat before blockers are declared.
Untap target attacking creature and remove it from combat. Gain control of that creature until end of turn.

Snow-Covered Plains

Angelsong

Prevent all combat damage that would be dealt this turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Rakdos Guildgate

Rakdos Guildgate enters tapped.
{T}: Add {B} or {R}.

Haunting Hymn

Target player discards two cards. If you cast this spell during your main phase, that player discards four cards instead.

Mountain

Orzhov Guildgate

Orzhov Guildgate enters tapped.
{T}: Add {W} or {B}.

Serra's Hymn

At the beginning of your upkeep, you may put a verse counter on Serra's Hymn.
Sacrifice Serra's Hymn: Prevent the next X damage that would be dealt this turn to any number of targets, divided as you choose, where X is the number of verse counters on Serra's Hymn.

Firesong and Sunspeaker

Red instant and sorcery spells you control have lifelink.
Whenever a white instant or sorcery spell causes you to gain life, Firesong and Sunspeaker deals 3 damage to target creature or player.

Izzet Guildgate

Izzet Guildgate enters tapped.
{T}: Add {U} or {R}.

Banshee of the Dread Choir

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Whenever Banshee of the Dread Choir deals combat damage to a player, that player discards a card.

Harmonious Archon

Flying
Non-Archon creatures have base power and toughness 3/3.
When Harmonious Archon enters, create two 1/1 white Human creature tokens.

Jodah, Archmage Eternal

Flying
You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Chorus of Woe

Creatures you control get +1/+0 until end of turn.

Cylian Sunsinger

{R}{G}{W}: Cylian Sunsinger and each other creature with the same name as it get +3/+3 until end of turn.

Shipwreck Singer

Flying
{1}{U}: Target creature an opponent controls attacks this turn if able.
{1}{B}, {T}: Attacking creatures get -1/-1 until end of turn.

Song of the Worldsoul

Whenever you cast a spell, populate. (Create a token that's a copy of a creature token you control.)

Akoum Battlesinger

Haste
Whenever Akoum Battlesinger or another Ally you control enters, you may have Ally creatures you control get +1/+0 until end of turn.

Piper's Melody

Shuffle any number of target creature cards from your graveyard into your library.

Chorus of Might

Until end of turn, target creature gets +1/+1 for each creature you control and gains trample.

Song of Serenity

Creatures that are enchanted can't attack or block.

Invincible Hymn

Count the number of cards in your library. Your life total becomes that number.

Chorus of the Tides

Flying
Heroic — Whenever you cast a spell that targets Chorus of the Tides, scry 1. (To scry 1, look at the top card of your library, then you may put that card on the bottom.)

Sensei's Divining Top

{1}: Look at the top three cards of your library, then put them back in any order.
{T}: Draw a card, then put Sensei's Divining Top on top of its owner's library.

Songstitcher

{1}{W}: Prevent all combat damage that would be dealt this turn by target attacking creature with flying.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Sol Ring

Dimir Guildgate

Dimir Guildgate enters tapped.
{T}: Add {U} or {B}.

Reviving Melody

Choose one or both —
• Return target creature card from your graveyard to your hand.
• Return target enchantment card from your graveyard to your hand.

Songs of the Damned

Add {B} for each creature card in your graveyard.

Titania's Song

Each noncreature artifact loses all abilities and becomes an artifact creature with power and toughness each equal to its mana value. If Titania's Song leaves the battlefield, this effect continues until end of turn.

Angelic Chorus

Whenever a creature you control enters, you gain life equal to its toughness.

Swamp

Harmony of Nature

Tap any number of untapped creatures you control. You gain 4 life for each creature tapped this way.