Archmage Emeritus

Magecraft — Whenever you cast or copy an instant or sorcery spell, draw a card.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

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.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.