Goblin Electromancer

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

Mountain

Shock

Niv-Mizzet, Parun

This spell can't be countered.
Flying
Whenever you draw a card, Niv-Mizzet deals 1 damage to any target.
Whenever a player casts an instant or sorcery spell, you draw a card.

Etali, Primal Storm

Whenever Etali attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Negate

Niv-Mizzet, the Firemind

Flying
Whenever you draw a card, Niv-Mizzet deals 1 damage to any target.
{T}: Draw a card.

Swiftwater Cliffs

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {U} or {R}.

Ral, Caller of Storms

+1: Draw a card.
−2: Ral deals 3 damage divided as you choose among one, two, or three targets.
−7: Draw seven cards. Ral deals 7 damage to each creature your opponents control.

Dominus of Fealty

Flying
At the beginning of your upkeep, you may gain control of target permanent until end of turn. If you do, untap it and it gains haste until end of turn.

Island

Electrodominance

Electrodominance deals X damage to any target. You may cast a spell with mana value X or less from your hand without paying its mana cost.

Rekindling Phoenix

Flying
When this creature dies, create a 0/1 red Elemental creature token with "At the beginning of your upkeep, sacrifice this token and return target card named Rekindling Phoenix from your graveyard to the battlefield. It gains haste until end of turn."

Lutri, the Spellchaser

Companion — Each nonland card in your starting deck has a different name. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
Flash
When Lutri enters, if you cast it, copy target instant or sorcery spell you control. You may choose new targets for the copy.

Winged Words

This spell costs {1} less to cast if you control a creature with flying.
Draw two cards.