Sanctum of Eternity

{T}: Add {C}.
{2}, {T}: Return target commander you own from the battlefield to your hand. Activate only during your turn.

Emergence Zone

{T}: Add {C}.
{1}, {T}, Sacrifice Emergence Zone: You may cast spells this turn as though they had flash.

Little Girl

Decoction Module

Whenever a creature you control enters, you get {E} (an energy counter).
{4}, {T}: Return target creature you control to its owner's hand.

Dragon Mask

{3}, {T}: Target creature you control gets +2/+2 until end of turn. Return it to its owner's hand at the beginning of the next end step. (Return it only if it's on the battlefield.)

Umbilicus

At the beginning of each player's upkeep, that player may pay 2 life. If they don't, they return a permanent they control to its owner's hand.

Blood Clock

At the beginning of each player's upkeep, that player returns a permanent they control to its owner's hand unless they pay 2 life.

Obelisk of Undoing

{6}, {T}: Return target permanent you both own and control to your hand.

Vedalken Orrery

You may cast spells as though they had flash.

Winding Canyons

{T}: Add {C}.
{2}, {T}: You may cast creature spells this turn as though they had flash.

Erratic Portal

{1}, {T}: Return target creature to its owner's hand unless its controller pays {1}.