Sol Ring

Selesnya Signet

Gruul Signet

Arcane Signet

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

Boros Signet

Selvala, Explorer Returned

Parley — {T}: Each player reveals the top card of their library. For each nonland card revealed this way, add {G} and you gain 1 life. Then each player draws a card.

Selvala's Stampede

Council's dilemma — Starting with you, each player votes for wild or free. Reveal cards from the top of your library until you reveal a creature card for each wild vote. Put those creature cards onto the battlefield, then shuffle the rest into your library. You may put a permanent card from your hand onto the battlefield for each free vote.

Simic Signet

Kenrith, the Returned King

{R}: All creatures gain trample and haste until end of turn.
{1}{G}: Put a +1/+1 counter on target creature.
{2}{W}: Target player gains 5 life.
{3}{U}: Target player draws a card.
{4}{B}: Put target creature card from a graveyard onto the battlefield under its owner's control.

Chulane, Teller of Tales

Vigilance
Whenever you cast a creature spell, draw a card, then you may put a land card from your hand onto the battlefield.
{3}, {T}: Return target creature you control to its owner's hand.

Questing Phelddagrif

{G}: Questing Phelddagrif gets +1/+1 until end of turn. Target opponent creates a 1/1 green Hippo creature token.
{W}: Questing Phelddagrif gains protection from black and from red until end of turn. Target opponent gains 2 life.
{U}: Questing Phelddagrif gains flying until end of turn. Target opponent may draw a card.

Azorius Signet

Training Grounds

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Rakdos Signet

Izzet Signet

Biomancer's Familiar

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.
{T}: The next time target creature adapts this turn, it adapts as though it had no +1/+1 counters on it.

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

Dimir Signet

Orzhov Signet

Mathas, Fiend Seeker

Menace
At the beginning of your end step, put a bounty counter on target creature an opponent controls. For as long as that creature has a bounty counter on it, it has "When this creature dies, each opponent draws a card and gains 2 life."

Golgari Signet

Veteran Explorer

When Veteran Explorer dies, each player may search their library for up to two basic land cards, put them onto the battlefield, then shuffle.