Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. This land deals 1 damage to you.

Hallowed Fountain

({T}: Add {W} or {U}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Command Tower

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

Impede Momentum

Tap target creature and put three stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Glacial Fortress

This land enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Flooded Strand

{T}, Pay 1 life, Sacrifice this land: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Solitary Sanctuary

When this enchantment enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you tap an untapped creature an opponent controls, put a +1/+1 counter on target creature you control.

Sharae of Numbing Depths

When Sharae enters, tap target creature an opponent controls and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you tap one or more untapped creatures your opponents control, draw a card. This ability triggers only once each turn.

Dovin's Veto

This spell can't be countered.
Counter target noncreature spell.

Arcane Signet

Sea of Clouds

This land enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Freeze in Place

Tap target creature an opponent controls and put three stun counters on it. Scry 2. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Azorius Chancery

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Hylda of the Icy Crown

Whenever you tap an untapped creature an opponent controls, you may pay {1}. When you do, choose one —
• Create a 4/4 white and blue Elemental creature token.
• Put a +1/+1 counter on each creature you control.
• Scry 2, then draw a card.

Mjölnir, Storm Hammer

When Mjölnir enters, attach it to target legendary creature you control.
Whenever equipped creature attacks, tap target creature defending player controls and put a stun counter on it. Then Mjölnir deals damage to each opponent equal to the number of tapped creatures that opponent controls.
Equip {4}

Counterspell

Azorius Signet

Deserted Beach

This land enters tapped unless you control two or more other lands.
{T}: Add {W} or {U}.

Lost in the Maze

Flash
When this enchantment enters, tap X target creatures. Put a stun counter on each of those creatures you don't control. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Tapped creatures you control have hexproof.

Sensational Spider-Man

Whenever Sensational Spider-Man attacks, tap target creature defending player controls and put a stun counter on it. Then you may remove up to three stun counters from among all permanents. Draw cards equal to the number of stun counters removed this way.

Talisman of Progress

{T}: Add {C}.
{T}: Add {W} or {U}. This artifact deals 1 damage to you.

The Watcher in the Water

The Watcher in the Water enters tapped with nine stun counters on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)
Whenever you draw a card during an opponent's turn, create a 1/1 blue Tentacle creature token.
Whenever a Tentacle you control dies, untap up to one target Kraken and put a stun counter on up to one target nonland permanent.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Prairie Stream

({T}: Add {W} or {U}.)
This land enters tapped unless you control two or more basic lands.

Reliquary Tower

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Port Town

As this land enters, you may reveal a Plains or Island card from your hand. If you don't, this land enters tapped.
{T}: Add {W} or {U}.