Taniwha

Trample
Phasing (This phases in or out before you untap during each of your untap steps. While it's phased out, it's treated as though it doesn't exist.)
At the beginning of your upkeep, all lands you control phase out. (They phase in before you untap during your next untap step.)

Perplexing Test

Choose one —
• Return all creature tokens to their owners' hands.
• Return all nontoken creatures to their owners' hands.

Consuming Tide

Each player chooses a nonland permanent they control. Return all nonland permanents not chosen this way to their owners' hands. Then you draw a card for each opponent who has more cards in their hand than you.

Coveted Jewel

When Coveted Jewel enters, draw three cards.
{T}: Add three mana of any one color.
Whenever one or more creatures an opponent controls attack you and aren't blocked, that player draws three cards and gains control of Coveted Jewel. Untap it.

Negate

Arcane Signet

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

Aetherize

Return all attacking creatures to their owner's hand.

Vow of Flight

Enchant creature
Enchanted creature gets +2/+2, has flying, and can't attack you or planeswalkers you control.

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Counterspell

Evacuation

Return all creatures to their owners' hands.

Midnight Clock

{T}: Add {U}.
{2}{U}: Put an hour counter on Midnight Clock.
At the beginning of each upkeep, put an hour counter on Midnight Clock.
When the twelfth hour counter is put on Midnight Clock, shuffle your hand and graveyard into your library, then draw seven cards. Exile Midnight Clock.

Thought Vessel

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

Thran Dynamo

High Tide

Until end of turn, whenever a player taps an Island for mana, that player adds an additional {U}.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Relic of Legends

{T}: Add one mana of any color.
Tap an untapped legendary creature you control: Add one mana of any color.

Psychic Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, you scry 2.

Time and Tide

Simultaneously, all phased-out creatures phase in and all creatures with phasing phase out.

Faerie Slumber Party

Return all creatures to their owners' hands. For each opponent who controlled a creature returned this way, you create two 1/1 blue Faerie creature tokens with flying and "This creature can block only creatures with flying."

Worn Powerstone

Worn Powerstone enters tapped.
{T}: Add {C}{C}.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Whelming Wave

Return all creatures to their owners' hands except for Krakens, Leviathans, Octopuses, and Serpents.

Flood of Tears

Return all nonland permanents to their owners' hands. If you return four or more nontoken permanents you control this way, you may put a permanent card from your hand onto the battlefield.

Long River's Pull

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Counter target creature spell. If the gift was promised, instead counter target spell.

Khalni Gem

When Khalni Gem enters, return two lands you control to their owner's hand.
{T}: Add two mana of any one color.

Sol Ring

Gilded Lotus

Sunder

Mana Breach

Whenever a player casts a spell, that player returns a land they control to its owner's hand.