msem-instigator

Equipped creature gets +2/+1.
Equip {2}

As long as Jadycian Empath is on the battlefield or in your graveyard, it's a land in addition to its other types.
Sacrifice Jadycian Empath: Add one mana of any color.

Jagged Cairn enters tapped.
{T}: Add {R} or {G}.
{2}{R}{G}, {T}, Sacrifice Jagged Cairn: Draw a card.

{1}, {T}: Tap target creature.

Whenever Jak, Daring Vanguard or another legendary creature you control enters, creatures you control get +1/+0 and gain haste until end of turn.

Lionize {2}{R} ({2}{R}, Exile this card from your hand: Put a +1/+1 counter on target creature and it gains the following abilities until end of turn. You may cast this card on a later turn from exile.)
Double strike

Flying, trample
At the beginning of combat on your turn, goad all creatures with power 3 or less. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)
Whenever a creature deals combat damage to an opponent, put a +1/+1 counter on it.

Trample
Other creatures you control have base power and toughness 8/8.

Trample, haste
Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)

You gain 5 life. Then draw a card if you've lost life this turn.

Equipped creature gets +2/+0 and has “{T}, Unattach Javelin: It deals 2 damage to target creature.”
Equip {2}

Trample
Whenever a creature card is put into your graveyard from anywhere, put a +1/+1 counter on Jawbone, Ravenous Mutant.

Enspirit (As you cast this spell, you may exile a nonenchantment creature you control until this leaves the battlefield or fails to resolve. Reduce this spell's cost by the exiled card's mana value.)
{T}: The next creature spell you cast this turn has enspirit. When that creature enters, it becomes an enchantment in addition to its other types.

Menace
Inspired — Whenever Jeering Kit becomes untapped, target Fox you control gets +1/+1 until end of turn.

Audition for green, then audition for green. (Create a 1/1 Construct Actor creature token, a Scout Role giving 2/3 and vigilance, or a Warrior Role giving 3/2 and trample. Roles replace older ones.)

When Jerrold's Wretched Cure enters, search your library for a legendary green card, reveal it, put it into your hand, then shuffle.
At the beginning of your upkeep, up to one other target nonland permanent you control becomes an X/X Construct creature in addition to its other types until end of turn, where X is the number of card types among cards in your graveyard.

Creatures you control have “Whenever this creature attacks, put a +1/+1 counter on target creature with lesser power.”
At the beginning of each end step, if there are five or more +1/+1 counters among creatures you control, destroy up to one target artifact or enchantment.

Choose two —
• Attacking creatures target player controls get +2/+0 and gain first strike until end of turn.
• Jeska's Command deals 3 damage to target creature.
• Creatures target player controls without flying can't block this turn.
• Target player exiles the top card of their library. Until the end of their next turn, they may play that card.

[+2]: Up to one target creature gets +1/+0 and gains first strike and haste until end of turn.
[–3]: Jeska deals 3 damage to target creature. If that creature is an artifact, she deals 5 damage instead.
[–10]: You get an emblem with “Creatures you control get +2/+0.” and “All creatures have haste and can't block.”

Advance {2} (Cast this for {2} to advance it as it enters. {2}: Advance this as a sorcery.)
Equipped creature gets +X/+0 and has flying, where X is the number of times it and Jet Pack have advanced this turn.
Equip {1}

Haste
When Jetskate enters, if you've drawn two or more cards this turn, it deals 2 damage to any target.
Cycling {R} ({R}, Discard this card: Draw a card.)

Reach
Whenever another creature you control becomes the target of an instant or sorcery spell, that creature gets +3/+3 until end of turn.

Renown 1
Whenever a creature you control becomes renowned, exile the top card of your library. You may play that card this turn.

Players play with the top card of their libraries revealed.
At the beginning of your first main phase, add {G}{G} for each land card among cards on top of libraries.
Jindao, the Coiled Prophet gets +2/+2 for each creature card among cards on top of libraries.

You may look at the top card of your library any time.
Once during each of your turns, you may play a land from the top of your library as though you could play an additional land.
{3}{G}{G}: You may cast the top card of your library without paying its mana cost if it's a creature card. Activate only as a sorcery.