msem-instigator

Target creature blocks this turn if able. You may have it gain reach until end of turn.
Draw a card.

Look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library.

Equipped creature has “{1}, {T}: This creature deals 1 damage to any target.”
Whenever equipped creature deals damage to a creature with power 5 or greater, sacrifice Sling of the Meek. If you do, destroy that creature.
Equip {3}

Slinking Raider can't be blocked by creatures with greater power.
Whenever Slinking Raider deals damage to a player or noncreature permanent, put a +1/+1 counter on it.
Surpass {5}{R} ({5}{R}: Transform this creature.
This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Slipsand Oasis enters tapped unless you played it from exile.
{T}: Add {W} or {B}.

Slipstream Horizon enters tapped.
{T}: Add {U} or {R}.
{U}{R}, {T}, Sacrifice Slipstream Horizon: Conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

(Transform this if it's not attached to a creature. Pay {2}{W} as a sorcery to unattach it.)
Enchant creature you control
Slopestrider's Chariot's rider gets +1/+1 and has double strike.

First strike
{2}{R}: Monstrosity 2. (If this creature isn't monstrous, put two +1/+1 counters on it and it becomes monstrous.)

{T}: Add {C}.
{4}, {T}, Sacrifice Slyten Crystal Motherlode: Add {W}{U}{B}{R}{G}.

Destroy target enchantment. If it's a Curse, you gain 3 life.

You draw a card and you lose 1 life. Exile Small Luxuries.
At the beginning of your upkeep, you may return Small Luxuries from your graveyard to your hand.

Goad up to one target creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)
Draw a card.

Target creature can't block this turn. Smokescreen deals 2 damage to that creature's controller.

Equipped creature gets +0/+2 and has menace.
Equip {1}

{T}: Add {C}.
{T}: Add one mana of any color. You can't spend this to cast spells from your hand.

Target creature gains deathtouch and poisonous 1 until end of turn. (Whenever that creature deals combat damage to a player, that player gets a poison counter.)
Inscribe {1}{G} ({1}{G}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Exile the top card of each player's library. You may play one of those cards this turn.

Snow Drift enters tapped. When it does, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this, then you may put that card into your graveyard.)
{T}: Add {U}.
{4}{U}: Snow Drift becomes an Elemental creature. (This effect lasts indefinitely.)

At the beginning of your end step, you may put a progress counter on Snowclearer.
[PROGRESS 1-2] Sacrifice Snowclearer: Add {C}.
[PROGRESS 3+] Sacrifice Snowclearer: Add two mana of any one color.

{T}: Add {C}.
{T}, Pay 1 life: Add {R} or {W}.

Create a 1/1 blue Bird creature token with flying.
Inscribe {2}{U} ({2}{U}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

{T}: Add {C}. If Soaring Observatory entered this turn, add one mana of any color instead.
Tap three differently named untapped Academies you control: Add three mana in any combination of colors.

({T}: Add {G} or {U}.)
Soaring Rainforest enters tapped.
{1}, {T}: Add {G}{G} or {U}{U}.

({T}: Add {U} or {B}.)
Sodden Cavern enters tapped.