Paradise Mantle

Equipped creature has "{T}: Add one mana of any color."
Equip {1}

Daze

You may return an Island you control to its owner's hand rather than pay this spell's mana cost.
Counter target spell unless its controller pays {1}.

Mana Leak

Counter target spell unless its controller pays {3}.

Horseshoe Crab

Rewind

Counter target spell. Untap up to four lands.

Echoing Truth

Return target nonland permanent and all other permanents with the same name as that permanent to their owners' hands.

Negate

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Counterspell

Insectile Aberration

Delver of Secrets

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform Delver of Secrets.

Delver of Secrets // Insectile Aberration

Hermetic Study

Enchant creature
Enchanted creature has "{T}: This creature deals 1 damage to any target."

Serum Visions

Augur of Bolas

When Augur of Bolas enters, look at the top three cards of your library. You may reveal an instant or sorcery card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Dispel

Spell Pierce

Counter target noncreature spell unless its controller pays {2}.

Thought Scour

Target player mills two cards.
Draw a card.

Sword of Feast and Famine

Equipped creature gets +2/+2 and has protection from black and from green.
Whenever equipped creature deals combat damage to a player, that player discards a card and you untap all lands you control.
Equip {2}

Aetherize

Return all attacking creatures to their owner's hand.

Island

Relic of Progenitus

{T}: Target player exiles a card from their graveyard.
{1}, Exile Relic of Progenitus: Exile all graveyards. Draw a card.