Reflecting Pool

{T}: Add one mana of any type that a land you control could produce.

Ball Lightning

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice this creature.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Ray of Command

Untap target creature an opponent controls and gain control of it until end of turn. That creature gains haste until end of turn. When you lose control of the creature, tap it.

Mountain

Teferi's Veil

Whenever a creature you control attacks, it phases out at end of combat. (While it's phased out, it's treated as though it doesn't exist. It phases in before you untap during your next untap step.)

Straw Golem

When an opponent casts a creature spell, sacrifice this creature.

Memory Lapse

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.

Blood Frenzy

Cast this spell only before the combat damage step.
Target attacking or blocking creature gets +4/+0 until end of turn. Destroy that creature at the beginning of the next end step.

Incinerate

Incinerate deals 3 damage to any target. A creature dealt damage this way can't be regenerated this turn.

Mana Leak

Counter target spell unless its controller pays {3}.

Viashino Sandstalker

Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, return this creature to its owner's hand. (Return it only if it's on the battlefield.)

Fog Elemental

Flying (This creature can't be blocked except by creatures with flying or reach.)
When this creature attacks or blocks, sacrifice it at end of combat.

Caldera Lake

This land enters tapped.
{T}: Add {C}.
{T}: Add {U} or {R}. This land deals 1 damage to you.

Portent

Look at the top three cards of target player's library, then put them back in any order. You may have that player shuffle.
Draw a card at the beginning of the next turn's upkeep.

Gemstone Mine

This land enters with three mining counters on it.
{T}, Remove a mining counter from this land: Add one mana of any color. If there are no mining counters on this land, sacrifice it.