Gonna buy

Double Vision

Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copy.

Too Expensive for now

Steam Vents

({T}: Add {U} or {R}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Firebender Ascension

When this enchantment enters, create a 2/2 red Soldier creature token with firebending 1.
Whenever a creature you control attacking causes a triggered ability of that creature to trigger, put a quest counter on this enchantment. Then if it has four or more quest counters on it, you may copy that ability. You may choose new targets for the copy.

Seething Song

Blood Crypt

({T}: Add {B} or {R}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Ozai, the Phoenix King

Trample, firebending 4, haste
If you would lose unspent mana, that mana becomes red instead.
Ozai has flying and indestructible as long as you have six or more unspent mana.

Snap

Return target creature to its owner's hand. Untap up to two lands.

Twinning Staff

If you would copy a spell one or more times, instead copy it that many times plus an additional time. You may choose new targets for the additional copy.
{7}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Talisman of Creativity

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

Faerie Mastermind

Flash
Flying
Whenever an opponent draws their second card each turn, you draw a card.
{3}{U}: Each player draws a card.

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Zuko, Firebending Master

First strike
Firebending X, where X is the number of experience counters you have. (Whenever this creature attacks, add X {R}. This mana lasts until end of combat.)
Whenever you cast a spell during combat, you get an experience counter.

Dualcaster Mage

Flash
When this creature enters, copy target instant or sorcery spell. You may choose new targets for the copy.