{T}: Add {C}.
{4}: Rumbling Door becomes a 3/3 Golem creature with vigilance. It's still a land.

Enchant creature
Enchanted creature gets -1/-1.
Sacrifice an artifact: Destroy enchanted creature. Activate only as a sorcery.

Surface {U}. Scuttling Cicada surfaces transformed.

Secluded Hangar enters tapped unless you control a basic non-Forest land.
{T}: Add {G}.
{2}, {T}: Put a +1/+1 counter on target creature that entered this turn.

Whenever a basic land you control enters, put a +1/+1 counter on Seeker of New Horizons. If you control seven or more lands, bless that land.

Serpentine Woods enters tapped.
{T}: Add {B} or {G}.
{2}{B}{G}, {T}, Sacrifice Serpentine Woods: Draw a card.

{B}, Sacrifice Serrated Fossil: Choose a nonland card name. Target player reveals their hand and discards a card with that name if able. Activate only as a sorcery.
Surface {3}{B}{B}. Serrated Fossil surfaces transformed.

Shell Cove enters tapped.
{T}: Add {G} or {U}.
{9}{G/U}: Shell Cove becomes a 7/7 green and blue Leviathan creature with ward {3} until end of turn. It's still a land. This ability costs {X} less to activate, where X is your devotion to green and blue. Activate only once each turn.

Menace
Whenever Ship Shredder enters or you cast a spell from your graveyard, each opponent loses 2 life and you gain 2 life.

At the beginning of combat on your turn, you gain 1 life. If you control three or more Shrines, instead you gain 3 life.

{4}{B}: You draw a card and you lose 1 life. This ability costs {1} less to activate for each other Shrine you control. Activate only once each turn.

At the beginning of combat on your turn, each opponent mills two cards. If you control three or more Shrines, scry 2.

Sillaman District enters tapped unless you control a Forest, a Plains, and an Island.
{T}: Add {G}, {W}, or {U}.

Double strike

Silvereye Scout can't be blocked except by three or more creatures.

Flying, trample, lifelink
Ward—Pay 7 life.

Exile target creature or enchantment if its mana value is less than or equal to the number of spells named Singularity you've cast this game.

{T}: Add {C}.
{3}, {T}: Create a 1/1 white Golem creature token. Spend mana of three different colors to activate this ability.
{T}: Put a +1/+1 counter on target creature. It gains flying until end of turn. Activate only as a sorcery and only if you control ten or more permanents.

Flash
Flying
When Sleeper Strix enters, tap up to one target creature.
You may look at an additional card each time you surveil.

When Slumbering Grove enters, search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Spellcharge 8

When Soul-Guide Lantern enters, exile target card from a graveyard.
{T}, Sacrifice Soul-Guide Lantern: Exile each opponent's graveyard.
{1}, {T}, Sacrifice Soul-Guide Lantern: Draw a card.

When Sparks of a Revolution enters, create a 1/1 colorless Soldier creature token. It gains haste until end of turn.
Three or more sources you controlled dealt damage this turn.
A source you controlled dealt 3 or more damage this turn.

Counter target activated or triggered ability from a nonland source. If a creature's ability is countered this way, you may pay {1}{C}. If you do, exile that creature.

Whenever a Ruin you control becomes spellcharged, put a +1/+1 counter on Speaker of the Forebears.
Sacrifice Speaker of the Forebears: Add an amount of {R} equal to the number of +1/+1 counters on it.

Whenever you amp it up, target creature gets +1/+1 until end of turn. If this is the second time this ability has resolved this turn, put a +1/+1 counter on that creature instead.