Mass of Remains's power is equal to the total number of permanent cards you own in your graveyard and in exile.
Spellcharge 3

Miasmic Cove enters tapped.
{T}: Add {B} or {G}.
{4}{B/G}: Miasmic Cove becomes a 2/3 black and green Snake creature with deathtouch until end of turn. It's still a land. This ability costs {X} less to activate, where X is your devotion to black and green. Activate only once each turn.

Mirrormeld Spire has all abilities of land cards integrated onto permanents you control.
{T}: Add {C}.
{C}, {T}: Integrate the top card of target player's library.

Nascent Lightvein enters tapped.
As Nascent Lightvein enters, choose a color. Then if you control three permanents that could each produce a different color of mana, untap it.
{T}: Add one mana of the chosen color.

Nebulous Ring enters tapped.
{T}: Add {C} or {W}.
{1}, Discard Nebulous Ring: Scry 2.

Neglected Slums enters tapped.
{T}: Add {R} or {G}.
{4}: Make a pledge. Activate only as a sorcery.

Neo Stehlia enters tapped unless you control a basic non-Plains land.
{T}: Add {W}.
{2}{W}, {T}: Choose a creature type. Creatures you control of the chosen type get +1/+0 until end of turn.

Trample, ward {4}
Equipped creature gets +4/+4 and has trample and ward {4}.
Equip {4}
Spellcharge 8

Nessian Woods enters tapped.
{T}: Add {R} or {G}.
{6}{R/G}: Nessian Woods becomes a 5/4 red and green Dryad creature with trample until end of turn. It's still a land. This ability costs {X} less to activate, where X is your devotion to red and green. Activate only once each turn.

Nimbus of Thought enters tapped.
{T}: Add {U} or {R}.
{4}{U/R}: Until end of turn, Nimbus of Thought becomes a 3/3 blue and red Elemental creature with “Whenever this creature becomes tapped, you may discard a card. If you do, draw a card.” It's still a land. This ability costs {X} less to activate, where X is your devotion to blue and red. Activate only once each turn.

Your maximum hand size is zero.
Pay 1 life: Draw a card. Activate only as a sorcery.

Open Air Boardwalk enters tapped.
{T}: Add {G} or {W}.
{4}: Make a pledge. Activate only as a sorcery.

Ozzen Headquarters enters tapped.
{T}: Add {W} or {B}.
{T}, Discard another card named Ozzen Headquarters: Draw a card.

Indulgence
Whenever you indulge, create a tapped token that's a copy of Pagentry Golem.

Penrath District enters tapped unless you control a Mountain, a Forest, and a Plains.
{T}: Add {R}, {G}, or {W}.

{T}: Add one mana of any color.
{1}{VP}{VP}{VP}, {T}, Sacrifice Petabyte Prism: Draw two cards.

Indestructible
As long as your devotion to blue and black is less than seven, Phenax isn't a creature.
At the beginning of each end step, each opponent mills X cards, where X is the number of cards put into their graveyard from anywhere this turn. You gain life equal to the number of cards milled this way.

When Plasma Armory enters or leaves the battlefield, create a Weapon token.
{2}, Sacrifice Plasma Armory: Draw a card.

Pool of Light enters tapped unless you control a basic Plains or a basic Island.

Possibility Heights enters tapped.
{T}: Add {R} or {G}.
{T}, Discard another card named Possibility Heights: Draw a card.

Flying
Whenever you cast a spell, choose one of its colors that you haven't chosen this way this turn. Add one mana of that color.

Pristine Grounds enters tapped unless you control no other lands.
{T}: Add one mana of any type Pristine Grounds hasn't produced this game.

Whenever you cast a spell, you may pay {X}, where X is that spell's mana value. If you do, copy it. You may choose new targets for the copy. Do this only once each turn.