Command Tower

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

Swamp

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Golgari Signet

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Slip Through Space

Devoid (This card has no color.)
Target creature can't be blocked this turn.
Draw a card.

The Locust God

Flying
Whenever you draw a card, create a 1/1 blue and red Insect creature token with flying and haste.
{2}{U}{R}: Draw a card, then discard a card.
When The Locust God dies, return it to its owner's hand at the beginning of the next end step.

Birds of Paradise

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Forest

Niv-Mizzet, the Firemind

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

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

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.

Sol Ring

Obsessive Search

Draw a card.
Madness {U} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Rakdos Signet

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Glint-Eye Nephilim

Whenever this creature deals combat damage to a player, draw that many cards.
{1}, Discard a card: This creature gets +1/+1 until end of turn.

Arcane Signet

Mountain

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on this creature.
When this creature dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on this creature. (They can't be blocked as long as defending player controls an Island.)

Izzet Signet

Dimir Signet

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Bone Miser

Whenever you discard a creature card, create a 2/2 black Zombie creature token.
Whenever you discard a land card, add {B}{B}.
Whenever you discard a noncreature, nonland card, draw a card.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Simic Signet

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Gruul Signet

Island

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")