Coruscation Mage

Offspring {2} (You may pay an additional {2} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Mountain

Shore Up

Target creature you control gets +1/+1 and gains hexproof until end of turn. Untap it. (It can't be the target of spells or abilities your opponents control.)

Shock

Eroded Canyon

Eroded Canyon enters tapped.
When Eroded Canyon enters, it deals 1 damage to target opponent.
{T}: Add {U} or {R}.

Sleight of Hand

Look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library.

Remand

Counter target spell. If that spell is countered this way, put it into its owner's hand instead of into that player's graveyard.
Draw a card.

Valley Flamecaller

If a Lizard, Mouse, Otter, or Raccoon you control would deal damage to a permanent or player, it deals that much damage plus 1 instead.

Unsummon

Return target creature to its owner's hand.

Spirebluff Canal

Spirebluff Canal enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {R}.

Swiftwater Cliffs

Swiftwater Cliffs enters tapped.
When Swiftwater Cliffs enters, you gain 1 life.
{T}: Add {U} or {R}.

Island

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.

Burst Lightning

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Burst Lightning deals 2 damage to any target. If this spell was kicked, it deals 4 damage instead.

Reasonable Doubt

Counter target spell unless its controller pays {2}.
Suspect up to one target creature. (A suspected creature has menace and can't block.)