Seaside Citadel

Seaside Citadel enters the battlefield tapped.
{T}: Add {G}, {W}, or {U}.

Arcane Sanctum

Arcane Sanctum enters the battlefield tapped.
{T}: Add {W}, {U}, or {B}.

The Eleventh Hour

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Search your library for a Doctor card, reveal it, put it into your hand, then shuffle.
II — Create a Food token and a 1/1 white Human creature token with "Doctor spells you cast cost {1} less to cast."
III — Create a token that's a copy of target creature, except it's a legendary Alien named Prisoner Zero.

Plains

An Unearthly Child

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II, III — Reveal cards from the top of your library until you reveal a Doctor card, a card with doctor's companion, or a Vehicle card. Put that card into your hand and the rest on the bottom of your library in a random order.

Crumbling Necropolis

Crumbling Necropolis enters the battlefield tapped.
{T}: Add {U}, {B}, or {R}.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Nomad Outpost

Nomad Outpost enters the battlefield tapped.
{T}: Add {R}, {W}, or {B}.

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.)

Call to the Kindred

Enchant creature
At the beginning of your upkeep, you may look at the top five cards of your library. If you do, you may put a creature card that shares a creature type with enchanted creature from among them onto the battlefield, then you put the rest of those cards on the bottom of your library in any order.

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.)

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Sol Ring

Unlikely Meeting

Search your library for a Doctor card, reveal it, put it into your hand, then shuffle.

Twice Upon a Time

Cast this spell only if you control two or more Doctors.
Take an extra turn after this one. Exile Twice Upon a Time.

Twice Upon a Time // Unlikely Meeting

Sandsteppe Citadel

Sandsteppe Citadel enters the battlefield tapped.
{T}: Add {W}, {B}, or {G}.

Savage Lands

Savage Lands enters the battlefield tapped.
{T}: Add {B}, {R}, or {G}.

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.)

Opulent Palace

Opulent Palace enters the battlefield tapped.
{T}: Add {B}, {G}, or {U}.

Kindred Discovery

As Kindred Discovery enters the battlefield, choose a creature type.
Whenever a creature you control of the chosen type enters the battlefield or attacks, draw a card.

Romana II

Vigilance
{1}, {T}: Create a tapped token that's a copy of target token that entered the battlefield this turn.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Jungle Shrine

Jungle Shrine enters the battlefield tapped.
{T}: Add {R}, {G}, or {W}.

Adric, Mathematical Genius

{2}{U}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
Ultimate Sacrifice — {1}{U}, Sacrifice Adric: Counter target activated or triggered ability.
Doctor's companion (You can have two commanders if the other is the Doctor.)

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.)

Forest

Roaming Throne

Ward {2}
As Roaming Throne enters the battlefield, choose a creature type.
Roaming Throne is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Snow-Covered Forest

Island

Rukarumel, Biologist

As Rukarumel, Biologist enters the battlefield, choose a creature type.
Slivers you control and nontoken creatures you control are the chosen type in addition to their other creature types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 1/1 colorless Sliver creature token.

Frontier Bivouac

Frontier Bivouac enters the battlefield tapped.
{T}: Add {G}, {U}, or {R}.

The Five Doctors

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Search your library and/or graveyard for up to five Doctor cards, reveal them, and put them into your hand. If you search your library this way, shuffle. If this spell was kicked, put those cards onto the battlefield instead of putting them into your hand.

Rose Noble

Ward {2}
Whenever you cast a Doctor spell or creature spell with doctor's companion, draw a card.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Gallifrey Stands

When Gallifrey Stands enters the battlefield, return all Doctor cards from your graveyard to your hand.
At the beginning of your upkeep, you may put a Doctor creature card from your hand onto the battlefield. Then if you control thirteen or more Doctors, you win the game.

Mystic Monastery

Mystic Monastery enters the battlefield tapped.
{T}: Add {U}, {R}, or {W}.

Mountain

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.)