msem-instigator

Menagerie — When Grotto Guardian enters, if there are five or more creature types among creatures you control, target creature you don't control gets -2/-2 until end of turn.

Vigilance
{3}{G}, {T}: Target creature you control fights target creature you don't control.

Eureka! (At the beginning of each end step, you get a research counter if you cast a spell this turn. Then if you have eight or more research counters, remove them and create a Masterpiece token of your choice.)
{T}: Draw a card, then discard a card.

Enchant creature
When Strike Fear enters, draw a card.
When enchanted creature attacks, target creature can't block this turn.

Flying
Saki of the Sea and Sky gets +1/+1 for each card inscribed onto it and each permanent attached to it.

Reveal up to four cards you own from outside the game with the same name, then shuffle them into your main library.
Draw a card.

{T}: Add {C}.
{1}, {T}: Add {W}{B}.

Menace
Ward—Pay 3 life.
When Infernal Direwolf enters, it fights up to one target creature an opponent controls. Excess damage Infernal Direwolf deals this way is dealt to that creature's controller instead.

Whenever Insatiable Abomination or another Horror you control enters, each player mills four cards.
Exile a creature card from your graveyard: Tap target Horror you control. It gains indestructible until end of turn.

Flash

Exile the top five cards of your library. You may play Dragon cards exiled this way as long as they remain exiled. You may play other cards exiled this way until the end of your next turn.

Assault {3}{G} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Crushclaw Pulverizer assaults, you may destroy target artifact or enchantment.

{T}: Return target creature card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. That creature salvages a card. (Exile one from your graveyard until that creature leaves the battlefield. Whenever that creature deals combat damage to a player, put a card it salvaged into your hand.)

Whenever you cast a creature spell, create a 2/1 white Sand creature token with flying.
Whenever you cast an instant or sorcery spell, create a 3/1 red Sand creature token with haste.
Whenever you cast an enchantment or artifact spell, create a 2/2 blue Sand creature token with hexproof.
Whenever a land you control enters, create a 3/3 green Sand creature token.

Poisonous 1 (Whenever this creature deals combat damage to a player, that player gets a poison counter.)
Duskscale Marauder can't be blocked.

Create three 1/1 white Spirit creature tokens with flying.

Put a +1/+1 counter on each of up to X target creatures.
Augmented — If you've spent {W}{U}{B}{R}{G} to cast spells this turn, instead put three +1/+1 counters on each of those creatures. They gain trample until end of turn.

{T}, Pay 1 life: Add {G}.
{T}, Pay 1 life, Sacrifice Tropical Grove: Search your library for a Forest card, put it onto the battlefield tapped, then shuffle.

Creatures you control get +1/+1 until end of turn. You gain 3 life.
Memento {4}{W}{W} (You may cast this from your graveyard for {4}{W}{W}. If you do, put it onto the battlefield transformed after it resolves. Exile it if it would leave the battlefield or not resolve.)

When Seeker of Far-Off Lands enters, search target opponent's library for a land card, put it onto the battlefield tapped under your control, then that player shuffles.

Equipped creature gets +2/+2.
Art of war — At the beginning of your end step, if equipped creature dealt damage to an opponent this turn, you may return target creature card from your graveyard to your hand.
Equip {2}

Whenever one or more creature cards leave your graveyard, Hadik's Cohort deals 2 damage to target opponent.

Flying, haste
Venwyn, the Dragon's Fang can't block.
At the beginning of combat on your turn, you may pay {1}{R/G}. If you do, create a token that's a copy of target creature you control with mana value 3 or less, except it's not legendary and has haste. Exile that token at end of combat.

As an additional cost to cast this spell, discard your hand.
Purge four times, then you gain 1 life for each card in exile. (Exile two cards that share a type from graveyards. If you do, draw a card.)