msem-instigator

When Jaakuna Bloodsworn enters, any opponent may have it deal 3 damage to them. If a player does, sacrifice Jaakuna Bloodsworn.

{1}, {T}: Put a +1/+1 counter on Jade Sentinel. Activate only if you control a creature with power greater than Jade Sentinel's.

{T}: Add {C}.
{T}: Add {C}{C}. You can't spend this mana to cast spells or activate abilities of lands.

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.

({T}: Add {R} or {W}.)
Jagged Crag enters tapped.

Activated abilities you activate cost {3} less to activate. This effect can't reduce the mana in that cost to less than one mana.
You may spend any number of colors of mana to activate attain abilities of permanents you control.

Menace
Jara Champion can only attack or block alone.
Whenever one or more players lose life for the first time each turn, put a +1/+1 counter on Jara Champion.

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}

You may play lands from graveyards.
{9}{G}{G}: Put nine +1/+1 counters on Jirada, Elder of Caulte.

Indestructible
At the beginning of combat on your turn, you may untap target land you control. If you do, that land becomes an X/X green Beast creature with haste until end of turn, where X is the number of differently named lands you control. It's still a land.

Return target creature card from your graveyard to your hand. Catalyze. (The next spell you cast this turn costs {1} less to cast.)
Flashback {3}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

When Journey to Elrayin enters, journey, then choose a creature card name. (To journey, exile the top card of your library face up. Whenever a creature you control deals combat damage to a player, put a journeyed card you own into your hand.)
Whenever a creature you control with the chosen name deals combat damage to a player, journey.

Detain target creature. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)
Scry 1.

Jungle Hollow enters tapped.
When Jungle Hollow enters, you gain 1 life.
{T}: Add {B} or {G}.

Jungle Shrine enters tapped.
{T}: Add {R}, {G}, or {W}.

Target player sacrifices a legendary creature or planeswalker.

(Transcend as a sorcery to gain that type and a +1/+1 counter.)
Jutou enters with X +1/+1 counters on her.
{3}{G}: Demigod — You gain life equal to the greatest power among creatures you control.
{6}{G}: God — Search your library for a creature card with the same power as a creature you control, put it onto the battlefield, then shuffle.

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a spell that's three or more colors.

Flying
Once during each of your turns, whenever you cast a spell from your graveyard, you may draw a card and create a tapped Treasure token.

Equipped creatures you control get +1/+1.
Equip {2}

Prowess
You may activate inscribe abilities from your graveyard as though they were in your hand.

Kamito Pathseeker can't block.
{3}{R}, Exile Kamito Pathseeker from your graveyard: Return target instant or sorcery card from your graveyard to your hand.

Whenever you cast a noncreature spell, you may pay {R}. If you do, untap Kamito Rageweaver.
{T}: Kamito Rageweaver deals 1 damage to target player.

{T}: Kanaan Wardriver deals 1 damage to target creature you control. That creature gains haste until end of turn.