Cao Cao, Lord of Wei

{T}: Target opponent discards two cards. Activate only during your turn, before attackers are declared.

Rafiq of the Many

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever a creature you control attacks alone, it gains double strike until end of turn.

Sharuum the Hegemon

Flying
When Sharuum enters, you may return target artifact card from your graveyard to the battlefield.

Sun Quan, Lord of Wu

Creatures you control have horsemanship. (They can't be blocked except by creatures with horsemanship.)

Teferi, Mage of Zhalfir

Flash
Creature cards you own that aren't on the battlefield have flash.
Each opponent can cast spells only any time they could cast a sorcery.

Ulamog, the Infinite Gyre

When you cast this spell, destroy target permanent.
Indestructible
Annihilator 4 (Whenever this creature attacks, defending player sacrifices four permanents of their choice.)
When Ulamog is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Visara the Dreadful

Flying
{T}: Destroy target creature. It can't be regenerated.

Captain Sisay

{T}: Search your library for a legendary card, reveal that card, put it into your hand, then shuffle.

Doran, the Siege Tower

Each creature assigns combat damage equal to its toughness rather than its power.

Copy

Kiki-Jiki, Mirror Breaker

Haste
{T}: Create a token that's a copy of target nonlegendary creature you control, except it has haste. Sacrifice it at the beginning of the next end step.

Kresh the Bloodbraided

Whenever another creature dies, you may put X +1/+1 counters on Kresh, where X is that creature's power.

Mikaeus, the Lunarch

Mikaeus enters with X +1/+1 counters on it.
{T}: Put a +1/+1 counter on Mikaeus.
{T}, Remove a +1/+1 counter from Mikaeus: Put a +1/+1 counter on each other creature you control.

Omnath, Locus of Mana

You don't lose unspent green mana as steps and phases end.
Omnath gets +1/+1 for each unspent green mana you have.

Oona, Queen of the Fae

Faerie Rogue

Flying
{X}{U/B}: Choose a color. Target opponent exiles the top X cards of their library. For each card of the chosen color exiled this way, create a 1/1 blue and black Faerie Rogue creature token with flying.

Progenitus

Protection from everything
If Progenitus would be put into a graveyard from anywhere, reveal Progenitus and shuffle it into its owner's library instead.

From the Vault: Legends