Plains

Nadaar, Selfless Paladin

Vigilance
Whenever Nadaar enters or attacks, venture into the dungeon. (Enter the first room or advance to the next room.)
Other creatures you control get +1/+1 as long as you've completed a dungeon.

Guardian of Faith

Flash
Vigilance
When this creature enters, any number of other target creatures you control phase out. (Treat them and anything attached to them as though they don't exist until their controller's next turn.)

Teleportation Circle

At the beginning of your end step, exile up to one target artifact or creature you control, then return that card to the battlefield under its owner's control.

Divine Smite

Target creature or planeswalker an opponent controls phases out. If that permanent is black, exile it instead. (If it phases out, treat it and anything attached to it as though they don't exist until its controller's next turn.)

Potion of Healing

When this artifact enters, draw a card.
{W}, {T}, Sacrifice this artifact: You gain 3 life.

Minimus Containment

Enchant nonland permanent
Enchanted permanent is a Treasure artifact with "{T}, Sacrifice this artifact: Add one mana of any color," and it loses all other abilities. (If it was a creature, it's no longer a creature.)

Keen-Eared Sentry

You have hexproof. (You can't be the target of spells or abilities your opponents control.)
Each opponent can't venture into the dungeon more than once each turn.

Dawnbringer Cleric

When this creature enters, choose one —
• Cure Wounds — You gain 2 life.
• Dispel Magic — Destroy target enchantment.
• Gentle Repose — Exile target card from a graveyard.

Veteran Dungeoneer

When this creature enters, venture into the dungeon. (Enter the first room or advance to the next room.)

Portable Hole

When this artifact enters, exile target nonland permanent an opponent controls with mana value 2 or less until this artifact leaves the battlefield.

Priest of Ancient Lore

When this creature enters, you gain 1 life and draw a card.

Cave of the Frost Dragon

If you control two or more other lands, this land enters tapped.
{T}: Add {W}.
{4}{W}: This land becomes a 3/4 white Dragon creature with flying until end of turn. It's still a land.

Loyal Warhound

Vigilance
When this creature enters, if an opponent controls more lands than you, search your library for a basic Plains card, put it onto the battlefield tapped, then shuffle.

Cloister Gargoyle

When this creature enters, venture into the dungeon. (Enter the first room or advance to the next room.)
As long as you've completed a dungeon, this creature gets +3/+0 and has flying.

Moon-Blessed Cleric

Divine Intervention — When this creature enters, you may search your library for an enchantment card, reveal it, then shuffle and put that card on top.