msem-instigator

When Long Lost Cause enters, each opponent exiles a card from their hand or a creature they control.

Flying
Long-Finned Skywhale can block only creatures with flying.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever Lord Jared, the Griffin Knight attacks, put a +1/+1 counter on each other attacking creature you control.

Flying
When Lord Rokai becomes the target of a spell, sacrifice it.
Whenever you cast an instant or sorcery spell, you may pay {2}{U}. If you do, return Lord Rokai from your graveyard to the battlefield.

Prowess
Whenever you cast a noncreature spell, noncreature spells you cast cost {1} less to cast until end of turn.

(Transcend as a sorcery to gain that type and a +1/+1 counter.)
Lifelink
Demon spells you cast cost {B} less to cast and an additional 2 life to cast.
{3}{B/R}{B/R}: Demon
Discard your hand. Draw a number of cards equal to the greatest power among Demons you control.
{5}{U/B}{U/B}: Noble
Gain control of target creature. You lose life equal to its mana value.

When Lost Crew enters or dies, crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)

Lost Explorer has first strike as long as it's attacking.
{1}{B}, Exile Lost Explorer from your graveyard: Crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)

First strike, haste
Whenever Lothaire attacks, create a 0/0 colorless Reflection creature token that's tapped and attacking. Creatures you control get +1/+1 until end of turn.
{2}{R}{W}: Put a +1/+1 counter on each creature you control.

Trample
Lotusleaf Blade gets +1/+1 as long as you control another Warrior.

Motivate 2 (When this creature enters, you may motivate target creature with less power than this by putting two +1/+1 counters on it.)
Whenever a creature you control becomes motivated, you gain 2 life.

Flash (You may cast this spell any time you could cast an instant.)
{2}{G}: Luminescent Croaker gains indestructible until end of turn.

Whenever Luna enters or phases in, each player loses 1 life.
Whenever a player casts a spell or a creature attacks, Luna phases out.

When Lunar Defractor enters, each player discards a card.
Revive {5}{B}{B} ({5}{B}{B}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

{T}: Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
At the beginning of combat on your turn, you may exile a creature card from your graveyard. When you do, target creature with the same power as the exiled card can't be blocked this turn.

Whenever one or more creatures in Luocha Mentor's pack attack, each creature in its pack gets +1/+0 until end of turn. (Two or more creatures you control with equal power are in a pack.)

Reach
Lupine Skygrazer enters with a +1/+1 counter on it if three or more colors of mana were spent to cast it.

When Lurking Angler enters, if seven or more cards are in your graveyard, draw a card. Otherwise, mill two cards.

Menagerie — When Lurking Feralynx enters, if there are five or more creature types among creatures you control, you may search your library for a card named Lurking Feralynx, reveal it, put it into your hand, then shuffle.

Concord — Lurking Lahasia has first strike and lifelink as long as there are four or more card types among permanents you control.

When Lysander Jal enters, create a token that's a copy of another target noncreature permanent you control.
Whenever you cast a spell from your graveyard, return target permanent card from your graveyard to your hand.

Disgraced 2 (This enters with two -1/-1 counters. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
Whenever Madame Deficit attacks, you may tap target creature.

As an additional cost to cast this spell, discard a card or pay {2}.

Players can't sacrifice creatures to cast spells or activate abilities unless that player sacrifices an additional creature. The same is true for discarding cards and paying life.