Arcane Mischief

Island

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Prismatic Vista

{T}, Pay 1 life, Sacrifice Prismatic Vista: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Fiery Islet

{T}, Pay 1 life: Add {U} or {R}.
{1}, {T}, Sacrifice Fiery Islet: Draw a card.

Mountain Bandit

Arcane Signet

Arcane Signet // Arcane Signet

Abandoned Sarcophagus

You may cast spells that have a cycling ability from your graveyard.
If a card that has a cycling ability would be put into your graveyard from anywhere and it wasn't cycled, exile it instead.

Mountain

Swamp Mosquito

Flying
Whenever Swamp Mosquito attacks and isn't blocked, defending player gets a poison counter. (A player with ten or more poison counters loses the game.)

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Mountain Goat

Mountainwalk (This creature can't be blocked as long as defending player controls a Mountain.)

Acererak the Archlich

When Acererak the Archlich enters, if you haven't completed Tomb of Annihilation, return Acererak the Archlich to its owner's hand and venture into the dungeon.
Whenever Acererak the Archlich attacks, for each opponent, you create a 2/2 black Zombie creature token unless that player sacrifices a creature of their choice.

Aether Searcher

Reveal Aether Searcher as you draft it. Reveal the next card you draft and note its name.
When Aether Searcher enters, you may search your hand and/or library for a card with a name noted as you drafted cards named Aether Searcher. You may cast it without paying its mana cost. If you searched your library this way, shuffle.