msem-instigator

Rhapsody {4}{R}{R} (Pay {4}{R}{R} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
Double strike

Target opponent sacrifices a creature. Put a +1/+1 counter on up to one target creature you control.

Art of war — At the beginning of your end step, if Raiun Bay Junk dealt damage to an opponent this turn, put a +1/+1 counter on it.
Tap an untapped creature you control: Raiun Bay Junk becomes an artifact creature until end of turn.

At the beginning of combat on your turn, look at the top four cards of your library. You may put a creature card with mana value 3 or less from among them onto the battlefield. Put the rest on the bottom of your library in a random order.

As long as Inconspicuous Platypus is enchanted or equipped, he's a 3/3 legendary Platypus Rogue named Agent P and can't be blocked.

Trample
Other Bears you control get +2/+2.

Landfall — Whenever a land you control enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Each player sacrifices two creatures, then gains 2 life and draws a card for each creature they sacrificed this way.

Target creature you control gets +1/+1 and gains indestructible until end of turn.
Fabled {3}{W}{W} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that creature.)

As Battle for the Shield enters, choose Danuri or Fellor.
• Danuri — Soldiers you control get +0/+1 and have vigilance.
• Fellor — Warriors you control get +1/+0 and have first strike.

Target creature gets -3/-3 until end of turn. You gain 3 life. (Then exile this card. You may cast the creature later from exile.)

Distribute three +1/+1 counters among any number of creatures you control.
Metamorph {1}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)

{T}: Add {W}.
{W}, {T}: Target creature gains vigilance until end of turn.

This spell can't be countered.
If a spell or ability an opponent controls causes you to sacrifice Wellspring of Creation, you may put it on the top or bottom of its owner's library instead of putting it into that player's graveyard.

Kicker {U} (You may pay an additional {U} as you cast this spell.)
Counter target spell. If this spell was kicked, look at the top three cards of your library, then put them back in any order.

Exile target creature you control, then return that card to the battlefield under your control.

Knight creatures you control have vigilance.
{2}{G}{W}: Put a +1/+1 counter on each creature you control.

When Doomed Woodsman dies, create a 1/1 green Faerie Druid creature token with hexproof.

Whenever Inishtu, Desert Healer enters or attacks, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
At the beginning of your upkeep, if seven or more cards are in your graveyard, you may transform Inishtu.

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Young Tempter enters, you draw a card and you lose 1 life.

Create two Idol tokens, then counter target spell unless its controller pays {1} for each Idol you control. (They're artifacts with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Tap two untapped Elves you control: Add {G}{G}.
{6}{G}{G}: Create an 8/8 green Elemental creature token.

If a nontoken creature you control would die, you may exile it instead. If you do, create two 1/1 white Spirit creature tokens with flying.

Rhapsody {5}{W}{W} (Pay {5}{W}{W} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
Whenever Oltenen Paradise-Seeker attacks, up to one target creature's base power and toughness each become equal to Oltenen Paradise-Seeker's power and toughness until end of turn.

Golden Glade enters tapped.
{1}, {T}: Add two mana of any one color.