msem-instigator

Whenever Lakeside Trickster becomes tapped, up to one target creature phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

When Lammasu Roost enters, create a 2/2 blue Lammasu creature token with flying.
{3}{U}: Scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Choose one —
• Destroy target artifact. Lamplight Explosion deals 1 damage to each opponent.
• Lamplight Explosion deals 1 damage to each creature your opponents control.

{T}: Add {U}. Spend this mana only to activate an ability or cast an instant or sorcery spell.

Vigilance
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Reveal the top four cards of your library. You may put a creature card and/or a land card from among them into your hand. Put the rest into your graveyard, then discard a card if two cards were put into your hand this way.

When Landbirth Elemental enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

When Landbound Ritualist enters, you may put a land card from your hand or graveyard onto the battlefield tapped.

Lifelink
Disgraced 1 (This enters with a -1/-1 counter. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)

Lantern-Bearer Belle gets +2/+0 and has flying as long as you've sacrificed a permanent this turn.

Tribute 1 (As this creature enters, an opponent of your choice may put a +1/+1 counter on it.)
When Lasis Persecutor enters, if tribute wasn't paid, it gains deathtouch. (This effect lasts indefinitely.)

Destroy target creature.

Up to two target creatures can't block this turn.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

Deathtouch
Vanishing 4 (This creature enters with four time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)

When Last-Thought Feeder dies, fateseal 2. (To fateseal 2, look at the top two cards of an opponent's library, then put any number of them on the bottom of that player's library and the rest on top in any order.)

Flash
Flying
When Laughing Bird enters, you may return a creature you control to its owner's hand.

Trample
Whenever Lava Hellions attacks, you may have it consume. If you do, it deals 2 damage to defending player. (To consume, sacrifice another creature or exile a creature card from your graveyard.)

Lava Spill deals 2 damage to any target.
Look at the top three cards of your library. Put one on top and the rest on the bottom in any order.

{4}{R}, Sacrifice Lavahurler: It deals 5 damage to target player or planeswalker.

{2}{R}, Sacrifice Lavaspark Igniter: It deals 2 damage to target creature.

Menace

Counter target spell unless its controller pays {4}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Whenever a Role becomes attached to Lead Athlete or you cast a spell that targets it, put a +1/+1 counter on Lead Athlete.

Attacking creatures get +2/+0 until end of turn. If you control a legendary creature, those creatures also gain first strike until end of turn.

Whenever Leading Clergy attacks, you may pay {W}. If you do, audition for white. (Create a 1/1 Construct Actor creature token, a Scout Role giving 2/3 and vigilance, or a Cleric Role giving 2/2 and lifelink. Roles replace older ones.)