msem-instigator

{T}: Add {C}.
{3}{W}: Until end of turn, Llereaux's Lair becomes a 1/2 creature. It's still a land. It can't be blocked this turn if {U} was spent to activate this ability, has indestructible if {B} was spent, and gets +2/+1 if {R} was spent.

Lonely Aerie enters tapped.
{T}: Add {W} or {U}.
{W}{U}: Until end of turn, Lonely Aerie becomes a Bird creature with flying in addition to its other types.
Scavenge {W}{U}

Lonely Trail enters tapped.
{T}: Add {G} or {W}.
When Lonely Trail enters, you may put a loyalty counter on a planeswalker you control.

Lost Station enters tapped.
{T}: Add {U}.
{U}{U}: Until end of turn, Lost Station becomes a 2/2 Horror creature with “This creature can't be blocked.” Activate only if you're horrific.

{T}: Add {C}.
{2}, {T}, Sacrifice Lotus Barrens: Destroy target nonbasic land an opponent controls. You and that land's controller each create a colorless land token named Lotus Spring with “{T}: Add one mana of any color.”

Lotus Lake enters tapped.
{T}: Add {C}.
Landfall — {T}: Add one mana of any color. Activate only if a land you control entered this turn.

Love Letters enters with X stamp counters on it.
Whenever one or more creatures you control deal combat damage to a player, you may remove a stamp counter from Love Letters. If you do, draw a card.

{T}: Add {C}.
Motley — {T}: Add one mana of any color. Activate only if there are five or more names among nonland permanents you control.

({T}: Add {G}.)
Lumbering Hillock enters tapped.
Trample
{2}{G}{G}: Lumbering Hillock becomes a creature in addition to its other types until end of turn.

Whenever you cast a spell that's white, blue, black, or green, create a 1/1 white Soldier creature token.

Lush Coast enters tapped.
{T}: Add {G} or {U}.
{1}, {T}: Add one mana of any color.

({T}: Add {G} or {U}.)
Lush Oasis enters tapped unless you control a basic Forest or a basic Island.

Lush Outcrop enters tapped unless another player controls a land that could produce {R} or {G}.
{T}: Add {R} or {G}.

Lush Outskirts enters tapped.
{T}: Add {G} or {U}.
{3}{G}{U}: Until end of turn, Lush Outskirts becomes a 5/7 green and blue Plant creature with with ward {3} and “Whenever this creature attacks or blocks, torment yourself.” It's still a land. (To torment yourself, lose 3 life unless you discard a card or sacrifice a nonland permanent.)

Macabre Pools enters tapped. When it enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {U} or {B}.

If Madame Beatrice would leave the battlefield, exile her instead.
Whenever one or more creatures you control deal combat damage to a player, that player reveals their hand. You may cast a card from their hand without paying its mana cost.

As Magmatic Torrent enters, you may pay 2 life. If you don't, Magmatic Torrent enters tapped.
{T}, Sacrifice Magmatic Torrent: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Magnificent Palace enters tapped.
As Magnificent Palace enters, choose two colors.
{T}: Add one mana of any of the chosen colors.

({T}: Add {W}, {B}, or {G}.)
Majestic Dominion enters tapped.

Majestic Tomb enters tapped.
{T}: Add {B} or {R}.
When Majestic Tomb enters, you may put a loyalty counter on a planeswalker you control.

Enchant creature
Enchanted creature has first strike and trample.

{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color. Spend this mana only to cast a legendary spell or activate an ability of a legendary permanent.
{3}, {T}, Sacrifice Many-Voiced Tower: Search your library for a legendary card, reveal it, put it into your hand, then shuffle. Activate only if you control five or more differently named lands.

Flying, lifelink
Your opponents can't search libraries.
{B}, Pay 2 life, Discard a card: Search your library for a card, then shuffle and put that card on top.

{T}: Add {C}.
Tap five untapped Satrapies you control: Add six mana in any combination of colors.

Whenever Marshback Knights becomes the target of a spell or ability an opponent controls, counter it unless they pay {3}.
{1}{U}: Marshback Knights gains flying until end of turn.