Sanctum of the Sun

(Transforms from Azor's Gateway.)
{T}: Add X mana of any one color, where X is your life total.

Azor's Gateway

{1}, {T}: Draw a card, then exile a card from your hand. If cards with five or more different mana values are exiled with Azor's Gateway, you gain 5 life, untap Azor's Gateway, and transform it.

Azor's Gateway // Sanctum of the Sun

Niv-Mizzet, Supreme

Flying, hexproof from monocolored
Each instant and sorcery card in your graveyard that's exactly two colors has jump-start. (You may cast that card from your graveyard by discarding a card in addition to paying its other costs. Then exile it.)

Niv-Mizzet, Dracogenius

Flying
Whenever Niv-Mizzet deals damage to a player, you may draw a card.
{U}{R}: Niv-Mizzet deals 1 damage to any target.

Golgari Guildgate

This land enters tapped.
{T}: Add {B} or {G}.

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.

Simic Guildgate

This land enters tapped.
{T}: Add {G} or {U}.

Selesnya Guildgate

This land enters tapped.
{T}: Add {G} or {W}.

Orzhov Guildgate

This land enters tapped.
{T}: Add {W} or {B}.

Rakdos Guildgate

This land enters tapped.
{T}: Add {B} or {R}.

Niv-Mizzet, Guildpact

Flying, hexproof from multicolored
Whenever Niv-Mizzet deals combat damage to a player, it deals X damage to any target, target player draws X cards, and you gain X life, where X is the number of different color pairs among permanents you control that are exactly two colors.

Dimir Guildgate

This land enters tapped.
{T}: Add {U} or {B}.

Azorius Guildgate

This land enters tapped.
{T}: Add {W} or {U}.

Niv-Mizzet Reborn

Flying
When Niv-Mizzet enters, reveal the top ten cards of your library. For each color pair, choose a card that's exactly those colors from among them. Put the chosen cards into your hand and the rest on the bottom of your library in a random order.

Gruul Guildgate

This land enters tapped.
{T}: Add {R} or {G}.

Izzet Guildgate

This land enters tapped.
{T}: Add {U} or {R}.

Boros Guildgate

This land enters tapped.
{T}: Add {R} or {W}.

Niv-Mizzet, the Firemind

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