Progenitor Mimic

You may have Progenitor Mimic enter as a copy of any creature on the battlefield, except it has "At the beginning of your upkeep, if this creature isn't a token, create a token that's a copy of this creature."

Zedruu the Greathearted

At the beginning of your upkeep, you gain X life and draw X cards, where X is the number of permanents you own that your opponents control.
{U}{R}{W}: Target opponent gains control of target permanent you control.

Zada, Hedron Grinder

Whenever you cast an instant or sorcery spell that targets only Zada, Hedron Grinder, copy that spell for each other creature you control that the spell could target. Each copy targets a different one of those creatures.

Rings of Brighthearth

Whenever you activate an ability, if it isn't a mana ability, you may pay {2}. If you do, copy that ability. You may choose new targets for the copy.

Bazaar Trader

{T}: Target player gains control of target artifact, creature, or land you control.

Djinn of Infinite Deceits

Flying
{T}: Exchange control of two target nonlegendary creatures. You can't activate this ability during combat.

Rite of Replication

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Double Vision

Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copy.

Riku of Two Reflections

Whenever you cast an instant or sorcery spell, you may pay {U}{R}. If you do, copy that spell. You may choose new targets for the copy.
Whenever another nontoken creature you control enters, you may pay {G}{U}. If you do, create a token that's a copy of that creature.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Fractured Identity

Exile target nonland permanent. Each player other than its controller creates a token that's a copy of it.

Sculpting Steel

You may have Sculpting Steel enter as a copy of any artifact on the battlefield.

Donate

Target player gains control of target permanent you control.

Leveler

When Leveler enters, exile all cards from your library.

Wedding Ring

When Wedding Ring enters, if it was cast, target opponent creates a token that's a copy of it.
Whenever an opponent who controls an artifact named Wedding Ring draws a card during their turn, you draw a card.
Whenever an opponent who controls an artifact named Wedding Ring gains life during their turn, you gain that much life.

Darksteel Reactor

Indestructible (Effects that say "destroy" don't destroy this artifact.)
At the beginning of your upkeep, you may put a charge counter on Darksteel Reactor.
When Darksteel Reactor has twenty or more charge counters on it, you win the game.

Puca's Mischief

At the beginning of your upkeep, you may exchange control of target nonland permanent you control and target nonland permanent an opponent controls with equal or lesser mana value.

Harmless Offering

Target opponent gains control of target permanent you control.

Splinter Twin

Enchant creature
Enchanted creature has "{T}: Create a token that's a copy of this creature, except it has haste. Exile that token at the beginning of the next end step."

Hive Mind

Whenever a player casts an instant or sorcery spell, each other player copies that spell. Each of those players may choose new targets for their copy.