Urza's Incubator

As Urza's Incubator enters the battlefield, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

Kindred Boon

As Kindred Boon enters the battlefield, choose a creature type.
{1}{W}: Put a divinity counter on target creature you control of the chosen type.
Each creature you control with a divinity counter on it has indestructible.

Belbe's Portal

As Belbe's Portal enters the battlefield, choose a creature type.
{3}, {T}: You may put a creature card of the chosen type from your hand onto the battlefield.

And They Shall Know No Fear

Choose a creature type. Creatures you control of the chosen type get +1/+0 and gain indestructible until end of turn.

Crippling Fear

Choose a creature type. Creatures that aren't of the chosen type get -3/-3 until end of turn.

Tribal Forcemage

Morph {1}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Tribal Forcemage is turned face up, creatures of the creature type of your choice get +2/+2 and gain trample until end of turn.

Molten Echoes

As Molten Echoes enters the battlefield, choose a creature type.
Whenever a nontoken creature of the chosen type enters the battlefield under your control, create a token that's a copy of that creature. That token gains haste. Exile it at the beginning of the next end step.

Extinction

Destroy all creatures of the creature type of your choice.

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Realmwalker

Changeling (This card is every creature type.)
As Realmwalker enters the battlefield, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

Roaming Throne

Ward {2}
As Roaming Throne enters the battlefield, choose a creature type.
Roaming Throne is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

An-Zerrin Ruins

As An-Zerrin Ruins enters the battlefield, choose a creature type.
Creatures of the chosen type don't untap during their controllers' untap steps.

Kindred Charge

Choose a creature type. For each creature you control of the chosen type, create a token that's a copy of that creature. Those tokens gain haste. Exile them at the beginning of the next end step.

Door of Destinies

As Door of Destinies enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Kindred Dominance

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Steely Resolve

As Steely Resolve enters the battlefield, choose a creature type.
Creatures of the chosen type have shroud. (They can't be the targets of spells or abilities.)

Bloodline Shaman

{T}: Choose a creature type. Reveal the top card of your library. If that card is a creature card of the chosen type, put it into your hand. Otherwise, put it into your graveyard.

Didgeridoo

{3}: You may put a Minotaur permanent card from your hand onto the battlefield.

Cavern of Souls

As Cavern of Souls enters the battlefield, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Tsabo's Decree

Choose a creature type. Target player reveals their hand and discards all creature cards of that type. Then destroy all creatures of that type that player controls. They can't be regenerated.

Kindred Discovery

As Kindred Discovery enters the battlefield, choose a creature type.
Whenever a creature you control of the chosen type enters the battlefield or attacks, draw a card.

Urtet, Remnant of Memnarch

Whenever you cast a Myr spell, create a 1/1 colorless Myr artifact creature token.
At the beginning of combat on your turn, untap each Myr you control.
{W}{U}{B}{R}{G}, {T}: Put three +1/+1 counters on each Myr you control. Activate only during your turn.

Pact of the Serpent

Choose a creature type. Target player draws X cards and loses X life, where X is the number of creatures they control of the chosen type.

Species Specialist

As Species Specialist enters the battlefield, choose a creature type.
Whenever a creature of the chosen type dies, you may draw a card.

Kindred Summons

Choose a creature type. Reveal cards from the top of your library until you reveal X creature cards of the chosen type, where X is the number of creatures you control of that type. Put those cards onto the battlefield, then shuffle the rest of the revealed cards into your library.

Vanquisher's Banner

As Vanquisher's Banner enters the battlefield, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Reflections of Littjara

As Reflections of Littjara enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Raise the Palisade

Choose a creature type. Return all creatures that aren't of the chosen type to their owners' hands.