At the beginning of your upkeep, exile the top three cards of your library. Each opponent secretly chooses a number 0 or greater. Then those numbers are revealed. Choose an opponent with the highest number. Itazura deals that much damage to them, then they may cast a spell from among those cards without paying its mana cost. You put a card from among them that wasn't cast this way into your hand.

0: Create a 1/1 white Cat creature token with ": Put a loyalty counter on each planeswalker you control."
−1: Look at the top six cards of your library. You may reveal a planeswalker or basic Plains card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
−8: Create ten Scryb Sprites tokens. (They're 1/1 Faerie creatures with flying.)
Worzel, the Protector can be your commander.

Each Beast, Camel, Horse, Elephant, and Wolf creature you control is a Mount in addition to its other types and has saddle 2. (Tap any number of other creatures you control with total power 2 or more: That Mount becomes saddled until end of turn. Saddle only as a sorcery.)
Whenever a saddled creature you control attacks, it gets +2/+2 until end of turn. Draw a card. Create a Food token.

When Nephilim Epochal enters, search your library for a Nephilim card, reveal it, put it into your hand, then shuffle.
Nephilim you control get +1/+1 for each other Nephilim you control and can't be blocked by monocolored creatures.

Shadow (This creature can block or be blocked by only creatures with shadow.)
Attacking Ninjas and Rogues you control have deathtouch.
Whenever one or more Ninjas and/or Rogues you control deal combat damage to a player, create a 1/1 black Rat Rogue creature token.

Other Phyrexians you control get +1/+1.
Each Equipment you control has living weapon. (Whenever an Equipment you control enters, create a 0/0 black Phyrexian Germ creature token, then attach that Equipment to it.)

The first nonlegendary creature spell you cast each turn has demonstrate. (When you cast that spell, you may copy it. If you do, choose an opponent to also copy it. Each copy becomes a token.)

Each other creature you control gets +3/+3 as long as it's not attacking or blocking.
Creature spells you control and creature cards you own in any zone other than the battlefield or the stack get +3/+3.

Whenever a source you control deals damage, if at least one permanent or player was dealt exactly 2 of that damage, exile the top card of your library. You may play it until the end of your next turn.
, , Exile two cards from your graveyard: Matoc deals 2 damage to any other target.

Whenever another creature you control enters, you lose 1 life and add .

Rulebreaker — A deck with this commander can have Phyrexian cards of any color identity and any basic land cards.
Phyrexian creatures you control have menace and lifelink.

Istvan attacks each combat if able.
Prevent all damage that would be dealt to Istvan by creatures.
Whenever a creature an opponent controls dies, put two +1/+1 counters on Istvan.

Vigilance, trample
At the beginning of your end step, each player may create a tapped land token named Sanctum with ": Add one mana of any color." Each opponent who does can't attack you during their next turn.

Whenever you discard one or more cards at random, select one or more targets at random, choose one or more modes at random, flip one or more coins, or roll one or more dice, put a +1/+1 counter on Chira and create a tapped Treasure token.

Menace
Whenever Miss Highwater deals combat damage to a player who doesn't have a contract counter, they may discard their hand. If they do, they draw seven cards and get a contract counter. For as long as they have a contract counter, when they lose the game, for each artifact and creature they controlled, create a token that's a copy of it.

Whenever you cast a noncreature spell, counter that spell. Create a number of 1/1 blue Merfolk creature tokens equal to the amount of mana spent to cast that spell.

When Euru, Acorn Scrounger enters, you may forage. When you do, conjure a card named Chitterspitter onto the battlefield.
Whenever one or more Squirrels you control deal combat damage to a player, you may sacrifice a token. If you do, put an acorn counter on each permanent you control named Chitterspitter.

Whenever Olinda enters or attacks, for each opponent, put an odor counter on up to one target creature that player controls without an odor counter on it. Each of those creatures has "At the beginning of your upkeep, you lose 2 life" for as long as it has an odor counter on it. (They continue to smell after Olinda has left the battlefield.)

Rulebreaker — If Tolabow, Loch Rascal is your commander, the color identity of instant and sorcery cards in your deck can include one color of your choice not in your commander's color identity, and your deck can have any basic land cards.
Whenever you cast an instant or sorcery spell, create a 1/1 blue and red Otter creature token with prowess. (Whenever you cast a noncreature spell, it gets +1/+1 until end of turn.)

Whenever The Madcap Jester attacks, each opponent exiles the top card of their library.
Whenever a spell or ability you control causes one or more cards to be exiled from an opponent's library, you may play those cards until the end of your next turn. Mana of any type can be spent to cast spells this way.

Whenever an artifact is put into a graveyard from the battlefield, put a number of +1/+1 counters equal to that artifact's mana value on Joven and Chandler.
, : Gain control of target artifact until end of turn. Untap it. It gains haste until end of turn.

Rulebreaker — A deck with this commander can have Angel cards of any color identity and any basic land cards.
Flying
Whenever Seluma deals combat damage to a player, return target Angel creature card from your graveyard to the battlefield.

Each nontoken creature you control that wasn't cast from your hand enters with two additional +1/+1 counters on it.
+1: Exile up to one other target permanent you control. At the beginning of the next end step, return that card to the battlefield under its owner's control.
−2: For each opponent, return up to one target nonland permanent that player controls to its owner's hand.
Venser, Visionary Traveler can be your commander.

Flying, trample, protection from Angels and from Archons
Players can't gain life.
When Balefang enters, target opponent creates a tapped Baneslayer Angel token. The token is goaded for the rest of the game. (It's a 5/5 Angel creature with flying, first strike, lifelink, and protection from Demons and from Dragons.)

+1: Create two tapped Powerstone tokens. (They're artifacts with ": Add . This mana can't be spent to cast a nonartifact spell.")
−X: Untap X target artifacts.
−6: Search your library for an artifact card, put it onto the battlefield, then shuffle.
Dyfed, the Guiding Hand can be your commander.

Menace
At the beginning of your end step, target opponent may draw four cards. If they do, look at that player's hand and you may cast a spell from their hand without paying its mana cost. If they don't, put two +1/+1 counters on Kuroki.

Trample, hexproof, indestructible

Protection from red
Whenever you cast your first spell during each opponent's turn, draw three cards, then put two cards from your hand on top of your library in any order.

Hexproof
When Autumn Willow enters, create a 1/1 green Forest Dryad land creature token. (It's affected by summoning sickness.)
Whenever you tap a land creature for mana, add an additional .

+2: Arzakon deals 3 damage to any other target.
−3: Create a Black Lotus token. (It's a artifact with ", Sacrifice this token: Add three mana of any one color.")
−7: Each player shuffles their hand and graveyard into their library, then draws seven cards.
Arzakon can be your commander.

+2: Create a 2/2 black Zombie creature token.
0: You may sacrifice a creature. If you do, add .
−5: Create a Lord of the Pit token. (It's a 7/7 Demon creature with flying, trample, and "At the beginning of your upkeep, sacrifice another creature. If you can't, this token deals 7 damage to you.")
Thomil, the Destroyer can be your commander.

Trample, indestructible
When Tresserhorn's Lord enters, sacrifice him unless you sacrifice three creatures, pay 3 life, and have target opponent draw three cards.
Whenever you sacrifice a creature, draw a card.

Whenever a creature dies, target opponent loses 1 life and you gain 1 life.
+1: Goad up to two target creatures.
−6: Each opponent exiles the top two cards of their library. Until end of turn, you may play those cards without paying their mana costs.
Sifa Grent can be your commander.

Shadow (This creature can block or be blocked by only creatures with shadow.)
Whenever The Weaver King deals combat damage to a player, they mill that many cards. Then for each opponent, put a creature card from that player's graveyard that was put there from their library this turn onto the battlefield under your control.

When Chief Magistrate of Mercadia enters, you become the monarch.
At the beginning of your upkeep, create a 2/1 red Goblin creature token with haste. Then if you're the monarch, for each creature token you control, create a token that's a copy of it.

Rulebreaker — A deck with this commander can have artifact creature and Equipment cards of any color identity and any basic land cards.
Whenever you cast an artifact creature or Equipment spell, you may copy that spell. Do this only once each turn. (The copy becomes a token.)