Lonis, Cryptozoologist

Whenever another nontoken creature you control enters, investigate.
{T}, Sacrifice X Clues: Target opponent reveals the top X cards of their library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield under your control. That player puts the rest on the bottom of their library in a random order.

Thriving Grove

This land enters tapped. As it enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Rewind

Counter target spell. Untap up to four lands.

Scene of the Crime

This land enters tapped.
{T}: Add {C}.
{T}, Tap an untapped creature you control: Add one mana of any color.
{2}, Sacrifice this land: Draw a card.

Stormcatch Mentor

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Instant and sorcery spells you cast cost {1} less to cast.

Follow Him

Investigate X times. (Then exile this card. You may cast the creature later from exile.)

James, Wandering Dad

{T}: Add {C}{C}. Spend this mana only to activate abilities.

James, Wandering Dad // Follow Him

Conduit Pylons

When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Lush Oasis

This land enters tapped.
When this land enters, it deals 1 damage to target opponent.
{T}: Add {G} or {U}.

Investigator's Journal

This artifact enters with a number of suspect counters on it equal to the greatest number of creatures a player controls.
{2}, {T}, Remove a suspect counter from this artifact: Draw a card.
{2}, Sacrifice this artifact: Draw a card.

Five Hundred Year Diary

Five Hundred Year Diary enters tapped.
{T}: Add {U} for each Clue you control.
{2}, Sacrifice Five Hundred Year Diary: Draw a card.

Geyser Drake

Flying
During turns other than yours, spells you cast cost {1} less to cast.

Jenny Flint

Partner with Madame Vastra
First strike
Training (Whenever this creature attacks with another creature with greater power, put a +1/+1 counter on this creature.)
Whenever you sacrifice a Clue or Food, put a +1/+1 counter on another target creature you control.

Rodeo Pyromancers

Whenever you cast your first spell each turn, add {R}{R}.

Dreamroot Cascade

This land enters tapped unless you control two or more other lands.
{T}: Add {G} or {U}.

Thriving Isle

This land enters tapped. As it enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Mocking Sprite

Flying
Instant and sorcery spells you cast cost {1} less to cast.

Madame Vastra

Partner with Jenny Flint (When this creature enters, target player may put Jenny Flint into their hand from their library, then shuffle.)
Madame Vastra must be blocked if able.
Whenever a creature dealt damage by Madame Vastra this turn dies, create a Clue token and a Food token.

Ulvenwald Mysteries

Whenever a nontoken creature you control dies, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Whenever you sacrifice a Clue, create a 1/1 white Human Soldier creature token.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Byway Courier

When this creature dies, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Mirage Mesa

This land enters tapped. As it enters, choose a color.
{T}: Add one mana of the chosen color.