Eminence — As long as The Unknown Wizard is in the command zone or on the battlefield, other playtest cards you cast cost less to cast.
Whenever The Unknown Wizard enters or attacks, look at the top ten cards of your library. You may put a legendary playtest card from among them onto the battlefield. Put the rest on the bottom in a random order.

: Choose target playtest card. Increase or decrease a number of your choice on it by one for as long as it remains on the stack or battlefield.
: Reveal the top 8 cards of your library. Put each playtest card among them into your hand, and the rest on the bottom of your library in a random order.

You may play Barce and any other legend with one color identity or less as your commanders as though they each had partner.
Whenever another legendary creature you control dies, you may put it into your command zone. It replaces one of your commanders.

When Polis the Planeshifter enters the battlefield, choose a plane at random from among all planechase planes. Polis the Planeshifter has all abilities of the last chosen plane. (Rolls of the planar die don't affect Polis.)
: Flip a coin. If you win the flip, do Polis the Planeshifter's chaos ensues effect. If you lose the flip, choose a new plane for Polis the Planeshifter.

If the Mirrans won the Unknown event on February 17th, 2023, Phila, Unsealed is also a Rebel with "You can't get poison counters," and has ": Exile target artifact."
If the Phyrexians won that event, Phila is also a Phyrexian with "Other Phyrexians you control get +1/+1 and gain Toxic 1."

As Minnea, Planar Tourist enters the battlefield, choose a plane.
Spells from the chosen plane cost , , , , or less to cast. (They're from the chosen plane if it's clear beyond doubt from the name, art, flavor text, or whatever extensive research you've done and can show that they're from that plane.)

Changeling (This card is every creature type.)
As the game begins, if this creature is your commander, choose two creature types. For the rest of the game, treat those two types like they're the same among your creatures and creature cards everywhere.
, : Choose a creature type. Draw a card for each creature you control of that type.

Whenever you cast a signed spell or play a signed land, copy it. (A signed card is a card signed by its artist, designer, or someone else it's strongly associated with.)
Discard a signed card: Destroy target creature with a name that has a five or fewer letter length difference from the person who signed the discarded card.

Spells you cast cost less to cast if they were originally printed in the following expansions or associated commander decks, depending on who won the Unknown event on February 18th, 2023:
Mirran Victory — Mirrodin, Darksteel, Fifth Dawn, and Scars of Mirrodin.
Phyrexian Victory — Mirrodin Besieged, New Phyrexia, All Will be One, and March of the Machine.

Gen gets +1/+1 for each different year of release among other nontoken permanents you control. (For example, if a card was released in 1993, that's one year of release. Specific editions matter.)
Whenever Gen attacks, if its power is 30 or greater, you win the game.

Horsemanship
The Horizon Seeker gets +1/+1 for each different named keyword and ability word among permanents you control and instant or sorcery cards in your graveyard. (For example, flying, landfall, and scry count. Flavor words, like "Magical Tinkering", or game terms like "enchant creature" and "mana" do not.)