msem-instigator

Search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

Any number of target creatures you control each have base power and toughness 3/3 and become Beasts in addition to their other types until end of turn.
Reconstruct {2}{G}{G} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

Create an X/X Elemental creature token that's all colors.
Reconstruct {X}{G}{G}{G} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

Creatures you control get +4/+4 and gain trample until end of turn.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

When Life's Harbinger dies, you may put a +1/+1 counter on target creature you control.
{T}: Add {G}.

At the beginning of your upkeep, put a brush counter on Life's Work, exile cards from the top of your library until you exile a card with mana value greater than or equal to the number of brush counters on Life's Work, then put that card into your hand.

{3}{G}: Put a +1/+1 counter on Lifecaller Dryad.

{T}: Add one mana of any color.
{2}, {T}: Choose a color. Add X mana of the chosen color, where X is the number of permanents you control that could produce mana of that color.

Reach (This creature can block creatures with flying.)
Whenever Lifespinner Spider blocks or becomes blocked by a creature with flying, you gain 1 life.

Reach
Each other creature you control gets +1/+1 for each +1/+1 counter on it.

As an additional cost to cast this spell, discard a card.
Return target card from your graveyard to your hand.

Target creature gets +X/+X and gains trample until end of turn, where X is the number of lands you control.
Fabled {4}{R}{G} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that creature.)

Light the Fuse deals 3 damage to target creature or planeswalker. Whenever a permanent dealt damage by Light the Fuse this turn dies this turn, repeat that process.

When Lightblessed Claymore enters, attach it to target creature you control.
Equipped creature gets +2/+0 and has lifelink.
Equip {4}

Activated abilities cost {1} more to activate unless they're mana abilities.

Haste
At the beginning of each end step, if Lightning Ox dealt damage this turn, sacrifice it.

Lightning Ripple deals 4 damage divided as you choose among any number of target creatures and/or planeswalkers.

Lightning Strike deals 3 damage to any target.

If you would harmonize while this spell is on the stack, you may instead put three thunder counters on this spell.
Lightning and Thunder deals X damage to any target, where X is 3 plus the number of thunder counters on Lightning and Thunder.

Whenever Lightseeker Nymph perseveres, search your library for a basic land card, put it onto the battlefield tapped, then shuffle. (A creature perseveres when it survives damage.)

You may have Ligneous Enormity assign its combat damage as though it weren't blocked.
Madness {3}{G}{G} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Hexproof from spells cast from a graveyard
If a creature you control would die and that creature was the target of an instant or sorcery spell this turn, you may put it on top of its owner's library instead.

First mate — Each nonland card in your starting deck has “+1/+1 counter” or “harmonize” in its printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Once each turn, if one or more +1/+1 counters would be put on a permanent you control, you may put twice that many of those counters on it instead.
Once each turn, if you would trigger a harmony ability of a permanent you control, you may have that ability trigger twice instead.

Advance {2} (Cast this for {2} to advance it as it enters. {2}: Advance this as a sorcery.)
Equipped creature gets +1/+1 for each artifact you control.
Equipped creature must be blocked by an additional creature for each time it and this artifact have advanced this turn to be blocked.
Equip {3}

Haste
Deploy 5 (As this enters, you may tap any number of other creatures you control with total power 5 or more.)
When Line Officer enters deployed, it deals 3 damage to each creature your opponents control.