The Seventh Doctor

Whenever The Seventh Doctor attacks, choose a card in your hand. Defending player guesses whether that card's mana value is greater than the number of artifacts you control. If they guessed wrong, you may cast it without paying its mana cost. If you don't cast a spell this way, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Jamie McCrimmon

Trample
Whenever you cast a historic spell, Jamie McCrimmon gets +X/+X until end of turn, where X is that spell's mana value. (Artifacts, legendaries, and Sagas are historic.)
Doctor's companion (You can have two commanders if the other is the Doctor.)

Donna Noble

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
Whenever Donna Noble or a creature it's paired with is dealt damage, Donna Noble deals that much damage to target opponent.
Doctor's companion (You can have two commanders if the other is the Doctor.)

The Rani

Whenever The Rani enters or attacks, create a red Aura enchantment token named Mark of the Rani attached to another target creature. That token has enchant creature and "Enchanted creature gets +2/+2 and is goaded."
Whenever a goaded creature deals combat damage to one of your opponents, investigate.

The First Doctor

When The First Doctor enters, search your library and/or graveyard for a card named TARDIS, reveal it, and put it into your hand. If you search your library this way, shuffle.
Whenever you cast a spell with cascade, put a +1/+1 counter on target artifact or creature.

Clara Oswald

Impossible Girl — If Clara Oswald is your commander, choose a color before the game begins. Clara Oswald is the chosen color.
If a triggered ability of a Doctor you control triggers, that ability triggers an additional time.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Yasmin Khan

{T}: Exile the top card of your library. Until your next end step, you may play it.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Jenny, Generated Anomaly

Double strike
Whenever Jenny deals combat damage to a player, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Vislor Turlough

Deal with the Black Guardian — When Vislor Turlough enters, you may have an opponent gain control of it. If you do, it's goaded for as long as they control it.
At the beginning of your end step, draw a card, then you lose life equal to the number of cards in your hand.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Graham O'Brien

Paradox — Whenever you cast a spell from anywhere other than your hand, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Doctor's companion (You can have two commanders if the other is the Doctor.)

Martha Jones

Woman Who Walked the Earth — When Martha Jones enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Whenever you sacrifice a Clue, Martha Jones and up to one other target creature can't be blocked this turn.
Doctor's companion (You can have two commanders if the other is the Doctor.)

The Fifth Doctor

Peaceful Coexistence — At the beginning of your end step, put a +1/+1 counter on each creature you control that didn't attack or enter this turn. Untap those creatures.

The Eighth Doctor

When The Eighth Doctor enters, mill three cards.
Once during each of your turns, you may play a historic land or cast a historic permanent spell from your graveyard. If you do, it gains "If this permanent would leave the battlefield, exile it instead of putting it anywhere else."

The War Doctor

Whenever one or more other permanents phase out and whenever one or more other cards are put into exile from anywhere, put a time counter on The War Doctor.
Whenever The War Doctor attacks, it deals damage equal to the number of time counters on it to any target. If a creature dealt damage this way would die this turn, exile it instead.

Dan Lewis

Noncreature, non-Equipment artifacts you control are Equipment in addition to their other types and have "Equipped creature gets +1/+0" and equip {1}.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Jo Grant

Each historic card in your hand has cycling {2}{W}. ({2}{W}, Discard that card: Draw a card.)
Whenever you cycle a card, put a +1/+1 counter on Jo Grant.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Tegan Jovanka

Brave Heart — Whenever you attack, target attacking historic creature gets +1/+1 and gains indestructible until end of turn. (Artifacts, legendaries, and Sagas are historic.)
Doctor's companion (You can have two commanders if the other is the Doctor.)

The Master, Gallifrey's End

Make Them Pay — Whenever a nontoken artifact creature you control dies, you may exile it. If you do, choose an opponent with the most life among your opponents. That player faces a villainous choice — They lose 4 life, or you create a token that's a copy of that card.

Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon enters, choose a creature type.
Spells of the chosen type you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Other creatures you control of the chosen type get +1/+1.

Rassilon, the War President

At the beginning of your upkeep, you lose 2 life and exile the top card of your library. You may play that card for as long as it remains exiled.
Each noncreature spell you cast from exile has conspire. (As you cast that spell, you may tap two untapped creatures you control that share a color with it. When you do, copy it and you may choose new targets for the copy.)

The Second Doctor

Players have no maximum hand size.
How Civil of You — At the beginning of your end step, each player may draw a card. Each opponent who does can't attack you or permanents you control during their next turn.

The Fugitive Doctor

When The Fugitive Doctor enters, investigate.
Whenever The Fugitive Doctor attacks, you may sacrifice a Clue. When you do, target instant or sorcery card in your graveyard gains flashback {2}{R}{G} until end of turn. (You may cast that card from your graveyard for its flashback cost. Then exile it.)

Susan Foreman

If you would planeswalk, instead look at the top two cards of your planar deck, put one on the bottom of your planar deck and the other on top, then planeswalk.
{T}: Add {G}.
Doctor's companion (You can have two commanders if the other is the Doctor.)

The Master, Mesmerist

{T}: Target creature an opponent controls with power less than or equal to The Master's power gains skulk until end of turn. Goad it. (A creature with skulk can't be blocked by creatures with greater power.)
Whenever a creature with skulk deals combat damage to one of your opponents, put a +1/+1 counter on The Master and draw a card.

Ryan Sinclair

Whenever Ryan attacks, exile cards from the top of your library until you exile a nonland card. You may cast the exiled card without paying its mana cost if it's a spell with mana value less than or equal to Ryan's power. Put the exiled cards not cast this way on the bottom of your library in a random order.
Doctor's companion (You can have two commanders if the other is the Doctor.)

K-9, Mark I

Negative — As long as K-9 is untapped, other legendary creatures you control have ward {1}.
Affirmative — {1}{U}, {T}: Target legendary creature can't be blocked this turn.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Nardole, Resourceful Cyborg

{T}: Add {U} for each counter on Nardole. Spend this mana only to cast noncreature spells.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)
Doctor's companion (You can have two commanders if the other is the Doctor.)

The Third Doctor

Trample
The Third Doctor gets +1/+1 for each noncreature token you control.
When The Third Doctor enters, create your choice of a Clue token, a Food token, or a Treasure token.

The Twelfth Doctor

The first spell you cast from anywhere other than your hand each turn has demonstrate. (When you cast that spell, you may copy it. If you do, choose an opponent to also copy it. A copy of a permanent spell becomes a token.)
Whenever you copy a spell, put a +1/+1 counter on The Twelfth Doctor.

The Eleventh Doctor

I. AM. TALKING! — Whenever The Eleventh Doctor deals combat damage to a player, you may exile a card from your hand with a number of time counters on it equal to its mana value. If it doesn't have suspend, it gains suspend.
{2}: Target creature with power 3 or less can't be blocked this turn.

The Master, Multiplied

Myriad
The "legend rule" doesn't apply to creature tokens you control.
Triggered abilities you control can't cause you to sacrifice or exile creature tokens you control.

The Sixth Doctor

Time Lord's Prerogative — Whenever you cast a historic spell, copy it, except the copy isn't legendary. This ability triggers only once each turn. (Artifacts, legendaries, and Sagas are historic. A copy of a permanent spell becomes a token.)

The Fourth Doctor

You may look at the top card of your library any time.
Would You Like A...? — Once each turn, you may play a historic land or cast a historic spell from the top of your library. When you do, create a Food token. (Artifacts, legendaries, and Sagas are historic.)

Peri Brown

The first historic spell you cast each turn has convoke. (Your creatures can help cast it. Each creature you tap while casting it pays for {1} or one mana of that creature's color.)
Doctor's companion (You can have two commanders if the other is the Doctor.)

River Song

Meet in Reverse — You draw cards from the bottom of your library rather than the top.
Spoilers — Whenever an opponent scries, surveils, or searches their library, put a +1/+1 counter on River Song. Then River Song deals damage to that player equal to its power.

Sarah Jane Smith

Whenever you cast a historic spell, investigate. This ability triggers only once each turn. (Artifacts, legendaries, and Sagas are historic. To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Doctor's companion (You can have two commanders if the other is the Doctor.)

The Tenth Doctor

Allons-y! — Whenever you attack, exile cards from the top of your library until you exile a nonland card. Put three time counters on it. If it doesn't have suspend, it gains suspend.
Timey-Wimey — {7}: Time travel three times. Activate only as a sorcery. (For each suspended card you own and each permanent you control with a time counter on it, you may add or remove a time counter. Then do it two more times.)

The Thirteenth Doctor

Paradox — Whenever you cast a spell from anywhere other than your hand, put a +1/+1 counter on target creature.
Team TARDIS — At the beginning of your end step, untap each creature you control with a counter on it.

The Valeyard

If an opponent would face a villainous choice, they face that choice an additional time. (They can make the same or different choices.)
While voting, you may vote an additional time.

Missy

Whenever another nonartifact creature dies, return it to the battlefield under your control face down and tapped. It's a 2/2 Cyberman artifact creature.
At the beginning of your end step, each opponent faces a villainous choice — Each artifact creature you control deals 1 damage to that opponent, or you draw a card and chaos ensues.

The Master, Formed Anew

Body Thief — When you cast this spell, you may exile a creature you control and put a takeover counter on it.
You may have The Master enter as a copy of a creature card in exile with a takeover counter on it.

The Ninth Doctor

Haste
Into the TARDIS — Whenever The Ninth Doctor becomes untapped during your untap step, you get an additional upkeep step after this step.

Rose Tyler

Rose Tyler gets +1/+1 for each time counter on it.
Bad Wolf — Whenever Rose Tyler attacks, put a time counter on it for each suspended card you own and each other permanent you control with a time counter on it.
Doctor's companion (You can have two commanders if the other is the Doctor.)