Creative Technique

Demonstrate (When you cast this spell, you may copy it. If you do, choose an opponent to also copy it.)
Shuffle your library, then reveal cards from the top of it until you reveal a nonland card. Exile that card and put the rest on the bottom of your library in a random order. You may cast the exiled card without paying its mana cost.

Arcane Signet

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

Sarinth Steelseeker

Whenever an artifact you control enters, look at the top card of your library. If it's a land card, you may reveal it and put it into your hand. If you don't put the card into your hand, you may put it into your graveyard.

Dire Fleet Daredevil

First strike
When Dire Fleet Daredevil enters, exile target instant or sorcery card from an opponent's graveyard. You may cast it this turn, and mana of any type can be spent to cast that spell. If that spell would be put into a graveyard, exile it instead.

Rocco, Street Chef

At the beginning of your end step, each player exiles the top card of their library. Until your next end step, each player may play the card they exiled this way.
Whenever a player plays a land from exile or casts a spell from exile, you put a +1/+1 counter on target creature and create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Inspiring Statuary

Nonartifact spells you cast have improvise. (Your artifacts can help cast those spells. Each artifact you tap after you're done activating mana abilities pays for {1}.)

Share the Spoils

When Share the Spoils enters and whenever an opponent loses the game, exile the top card of each player's library.
During each player's turn, that player may play a land or cast a spell from among cards exiled with Share the Spoils, and they may spend mana as though it were mana of any color to cast that spell. When they do, exile the top card of their library.

Kami of Whispered Hopes

If one or more +1/+1 counters would be put on a permanent you control, that many plus one +1/+1 counters are put on that permanent instead.
{T}: Add X mana of any one color, where X is Kami of Whispered Hopes's power.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Herd Baloth

Whenever one or more +1/+1 counters are put on Herd Baloth, you may create a 4/4 green Beast creature token.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Soul Partition

Exile target nonland permanent. For as long as that card remains exiled, its owner may play it. A spell cast by an opponent this way costs {2} more to cast.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Dusk Legion Duelist

Vigilance
Whenever one or more +1/+1 counters are put on Dusk Legion Duelist, draw a card. This ability triggers only once each turn.

Laelia, the Blade Reforged

Haste
Whenever Laelia, the Blade Reforged attacks, exile the top card of your library. You may play that card this turn.
Whenever one or more cards are put into exile from your library and/or your graveyard, put a +1/+1 counter on Laelia.

Rampage of the Clans

Destroy all artifacts and enchantments. For each permanent destroyed this way, its controller creates a 3/3 green Centaur creature token.

Conclave Mentor

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on that creature instead.
When Conclave Mentor dies, you gain life equal to its power.

Sol Ring

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.