Warped Devotion

Whenever a permanent is returned to a player's hand, that player discards a card.

Kormus Bell

All Swamps are 1/1 black creatures that are still lands.

Blanket of Night

Each land is a Swamp in addition to its other land types.

Dromar, the Banisher

Flying
Whenever Dromar deals combat damage to a player, you may pay {2}{U}. If you do, choose a color, then return all creatures of that color to their owners' hands.

Llawan, Cephalid Empress

When Llawan enters, return all blue creatures your opponents control to their owners' hands.
Your opponents can't cast blue creature spells.

Tameshi, Reality Architect

Whenever one or more noncreature permanents are returned to hand, draw a card. This ability triggers only once each turn.
{X}{W}, Return a land you control to its owner's hand: Return target artifact or enchantment card with mana value X or less from your graveyard to the battlefield. Activate only as a sorcery.

Shifting Sky

As this enchantment enters, choose a color.
All nonland permanents are the chosen color.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Opalescence

Each other non-Aura enchantment is a creature in addition to its other types and has base power and base toughness each equal to its mana value.

Distorting Lens

{T}: Target permanent becomes the color of your choice until end of turn.

Painter's Servant

As this creature enters, choose a color.
All cards that aren't on the battlefield, spells, and permanents are the chosen color in addition to their other colors.

Scuttlemutt

{T}: Add one mana of any color.
{T}: Target creature becomes the color or colors of your choice until end of turn.

Sol Ring

Plains

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Wash Out

Return all permanents of the color of your choice to their owners' hands.

Yavimaya, Cradle of Growth

Each land is a Forest in addition to its other land types.

Sway of Illusion

Any number of target creatures become the color of your choice until end of turn.
Draw a card.