msem-instigator

Whenever Bristled Wolverine attacks, it gets +1/+1 until end of turn.

{2}, Sacrifice Doctored Trail: Draw a card.
{T}, Sacrifice Doctored Trail: Destroy target Clue. If you do, draw a card.

Return X target creature cards with mana value 3 or less from your graveyard to the battlefield, then choose one of them and exile the rest.

Whenever a creature you control enters, you may have it get +1/+1 until end of turn. If you do, it fights target creature. (Each deals damage equal to its power to the other.)

{1}, {T}, Move a -1/-1 counter from another creature onto Zealous Bloodletter: Proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Hexproof
When Overburdened Trader enters, create three 1/1 colorless Construct artifact creature tokens.

Other creatures you control get +1/+1.
When Kotis, Promised General dies, you may return it to its owner's hand.

When Grave Wrangler enters, you may return target creature card from your graveyard to your hand.

Whenever you cast an instant or sorcery spell, create a Treasure Clue token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color” and “{2}, Sacrifice this artifact: Draw a card.)

Creatures you control gain vigilance until end of turn. After this main phase, there's an additional combat phase followed by an additional main phase.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)

When Festival Celebrants enters, put a +1/+1 counter on each creature you control.

Search your library for a legendary creature card, reveal it, put it into your hand, then shuffle. Then if this spell was foretold, you may put a creature card from your hand onto the battlefield.
Foretell {4}{G}{G}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Add {W}{U}{B}{R}{G}. Spend this mana only to cast spells from your graveyard or activate abilities of cards in your graveyard.

When Undead Servant enters, create a 2/2 black Zombie creature token for each card named Undead Servant in your graveyard.

Exile the top two cards of your library. Until the end of your next turn, you may play those cards. If this spell was cast from a graveyard, you may play cards this way without paying their mana costs.
Flashback {5}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Destroy all nonland permanents with mana value 3 or less.

{1}{R}: Performer of Desire gets +1/+1 and gains menace until end of turn. Then if its power is 4 or greater, you may transform it.

Return all nonland permanents to their owners' hands.

Enchant creature
When Twinklewings enters, draw a card.
Enchanted creature has flying.

Whenever you scry, put a +1/+1 counter on Shimmershell.

Flying, vigilance
When Guardian Grotesque dies, return up to one target nonland permanent to its owner's hand.
Foreshadow {6} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

Denouement deals damage to each creature and each planeswalker equal to the number of enchantments you control.

({T}: Add {U} or {B}.)
Muggy Mire enters tapped unless you control two or more basic lands.

Trample
Whenever Oshu deals combat damage to a player, gain control of target land that player controls. It becomes a 4/4 Elemental creature that's still a land.
As long as you control eight or more lands, Oshu and land creatures you control get +2/+2.