Horse

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

Copy

(This token can be used to represent a token that's a copy of a permanent.)

The Girl in the Fireplace

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create a 1/1 white Human Noble creature token with vanishing 3 and "Prevent all damage that would be dealt to this creature."
II — Create a 2/2 white Horse creature token with "Doctors you control have horsemanship." (They can't be blocked except by creatures with horsemanship.)
III — Whenever a creature you control deals combat damage to a player this turn, time travel.

Human Noble

Vanishing 3
Prevent all damage that would be dealt to this creature.

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.

Human

Doctor spells you cast cost {1} less to cast.

Treasure

{T}, Sacrifice this token: Add one mana of any color.

Alien Rhino

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.)

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

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.

Clue

{2}, Sacrifice this artifact: Draw a card.

Fugitive of the Judoon

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create a 1/1 white Human creature token with ward {2} and a 4/4 white Alien Rhino creature token.
II — Investigate.
III — You may exile a Human you control and an artifact you control. If you do, search your library for a Doctor card, put it onto the battlefield, then shuffle.