Teenage Mutant Ninja Turtles

Legendary Creature — Mutant Ninja Turtle

Whenever you put a counter on a creature you control, draw a card. This ability triggers only once each turn.

Mikey & Leo, Chaos & Order

Legendary Creature — Utrom Human Ninja

Whenever Krang & Shredder enter or attack, each opponent exiles cards from the top of their library until they exile a nonland card.
Disappear — At the beginning of your end step, if a permanent left the battlefield under your control this turn, you may cast a card exiled with Krang & Shredder without paying its mana cost.

Krang & Shredder

Legendary Creature — Human Wizard

Flash
When Renet enters, return each other nonland permanent that entered this turn to its owner's hand.

Renet, Temporal Apprentice

Mutant

When Jennika enters, create a 2/2 red Mutant creature token.
Plainscycling {2} ({2}, Discard this card: Search your library for a Plains card, reveal it, put it into your hand, then shuffle.)

Jennika, Bad Apple Big Sister

Legendary Creature — Boar Rhino Mutant

Whenever Bebop & Rocksteady attack or block, sacrifice a permanent unless you discard a card.

Bebop & Rocksteady

Menace
Whenever Don & Raph attack, the next noncreature spell you cast this turn has affinity for artifacts. (It costs {1} less to cast for each artifact you control.)

Don & Raph, Hard Science

Legendary Creature — Human Detective

Whenever April deals combat damage to a player, draw that many cards, then discard a card.

April, Reporter of the Weird

Legendary Creature — Human Berserker

Haste
When Casey Jones enters, look at the top four cards of your library. You may reveal an artifact card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Casey Jones, Jury-Rig Justiciar

Legendary Creature — Mutant Berserker Turtle

Alliance — Whenever another creature you control enters, Slash deals 2 damage to each opponent.
Whenever Slash attacks, create a 2/2 red Mutant creature token.

Slash, Reptile Rampager

Secret Lair Showcase Planes

Plane — Secret Lair

When you planeswalk to this plane and at the beginning of your upkeep, create a Map token. (It's an artifact with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.")
Whenever chaos ensues, draw two cards, then discard two cards. Untap up to three lands.

Fblthp: Completely, Utterly, Totally Lost

Secret Lair Drop

Basic Land — Forest

Forest

Instant

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Path to Exile

Artifact

Whenever you gain life, you may pay {X}, where X is less than or equal to the amount of life you gained. If you do, draw X cards.

Well of Lost Dreams

Draw two cards, then discard two cards. Untap up to three lands.

Frantic Search

Enchantment

Creatures don't untap during their controllers' untap steps.
Whenever a creature enters, untap all creatures.

Intruder Alarm

Land

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
This land enters tapped.
{T}: Add {U}.
{U}, {T}: You may play the exiled card without paying its mana cost if a library has twenty or fewer cards in it.

Shelldock Isle

Case of the Lost Witness

Legendary Creature — Homunculus

When Fblthp enters, draw a card. If it entered from your library or was cast from your library, draw two cards instead.
When Fblthp becomes the target of a spell, shuffle Fblthp into its owner's library.