MTG Niv to Light Deck by Folero

Companion — Your starting deck contains at least twenty cards more than the minimum deck size. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.) Flying When Yorion enters, exile any number of other nonland permanents you own and control. Return those cards to the battlefield at the beginning of the next end step.

Defender, hexproof {T}: Add one mana of any color.

When this creature enters, exile another target creature or artifact until this creature leaves the battlefield. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

When Omnath enters, draw a card. Landfall — Whenever a land you control enters, you gain 4 life if this is the first time this ability has resolved this turn. If it's the second time, add {R}{G}{W}{U}. If it's the third time, Omnath deals 4 damage to each opponent and each planeswalker you don't control.

Vigilance If a permanent entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time. Permanents entering don't cause abilities of permanents your opponents control to trigger.

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.

Whenever you cast a spell that's one or more colors, you may gain 1 life for each of that spell's colors. Do this only once each turn. {T}: Add one mana of any color.

Enchant Mountain you control When this Aura enters, exile target creature an opponent controls until this Aura leaves the battlefield. (That creature returns under its owner's control.)

When this enchantment enters and whenever you cast a spell with mana value 5 or greater, draw a card.

Flash Domain — This spell costs {1} less to cast for each basic land type among lands you control. When this enchantment enters, exile target nonland permanent an opponent controls until this enchantment leaves the battlefield.

Lightning Helix deals 3 damage to any target and you gain 3 life.

This spell can't be countered. Choose a nonland card name. Search target opponent's graveyard, hand, and library for any number of cards with that name and exile them. Then that player shuffles.

Exile all creatures. Incubate X, where X is the number of creatures exiled this way. (Create an Incubator token with X +1/+1 counters on it and "{2}: Transform this token." It transforms into a 0/0 Phyrexian artifact creature.)

As an additional cost to cast this spell, you may collect evidence 6. Destroy all creatures. If evidence was collected, exile a card from an opponent's graveyard. Then search its owner's graveyard, hand, and library for any number of cards with that name and exile them. That player shuffles, then draws a card for each card exiled from their hand this way.

Exile the top five cards of your library. You may play cards exiled this way until the end of your next turn. You may play an additional land this turn.

Converge — Search your library for a creature, instant, or sorcery card with mana value less than or equal to the number of colors of mana spent to cast this spell, exile that card, then shuffle. You may cast that card without paying its mana cost.

({T}: Add {W}.)

({T}: Add {U}.)

({T}: Add {B}.)

({T}: Add {R}.)

{T}: Add {G}. Channel — {1}{G}, Discard this card: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

({T}: Add {G}.)

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

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

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

({T}: Add {W}, {U}, or {B}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {U}, {B}, or {R}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {B}, {R}, or {G}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {R}, {G}, or {W}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {G}, {W}, or {U}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {R}, {W}, or {B}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {G}, {U}, or {R}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {U}, {R}, or {W}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

({T}: Add {B}, {G}, or {U}.) This land enters tapped. Cycling {3} ({3}, Discard this card: Draw a card.)

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.