Plains

Conspiracy

As Conspiracy enters the battlefield, choose a creature type.
Creatures you control are the chosen type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

Infernal Spawn of Infernal Spawn of Evil

Flying, first strike, trample
Once each turn, while you're searching your library, you may pay {1}{B}, reveal Infernal Spawn of Infernal Spawn of Evil from your library and say "I'm coming, too!" If you do, Infernal Spawn of Infernal Spawn of Evil deals 2 damage to a player of your choice.

A Real Handful

As long as one or more hands are touching A Real Handful, it gets +2/+2.
As long as two or more hands are touching A Real Handful, it has menace.
As long as three or more hands are touching A Real Handful, it has lifelink.

Wedding Festivity

Wedding Announcement

At the beginning of your end step, put an invitation counter on Wedding Announcement. If you attacked with two or more creatures this turn, draw a card. Otherwise, create a 1/1 white Human creature token. Then if Wedding Announcement has three or more invitation counters on it, transform it.

Wedding Announcement // Wedding Festivity

Adaptive Automaton

As Adaptive Automaton enters the battlefield, choose a creature type.
Adaptive Automaton is the chosen type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

Swamp

Little Girl

Meddling Kids

As Meddling Kids enters the battlefield, choose a word with four or more letters.
Spells with the chosen word in their text box can't be cast.

Obelisk of Urd

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
As Obelisk of Urd enters the battlefield, choose a creature type.
Creatures you control of the chosen type get +2/+2.

Xenograft

As Xenograft enters the battlefield, choose a creature type.
Each creature you control is the chosen type in addition to its other types.