msem-instigator

Choose one —
• Target player mills four cards.
• Draw a card.

Scavenger Holdout enters tapped.
When Scavenger Holdout enters, you may pay {3}. If you do, create two 1/1 green Scout creature tokens.
{T}: Add {C}.

Whenever you cast an enchantment spell, create a 1/1 white and black Bird creature token with flying and vigilance.
Whenever three or more creatures you control deal combat damage to a player, that player sacrifices a creature. If they can't, they discard a card.

{T}: Add {G} or one mana of any color among cards in your graveyard.

Fellor Vanguard gets +1/+1 as long as you control a Mountain.
{1}{R}: Fellor Vanguard gets +1/+0 until end of turn.

Aleud Beastmaster has frenzy X, where X is the number of unblocked attacking creatures you control. (Whenever it attacks and isn't blocked, it gets +X/+0 until end of turn.)

Once each turn, when a creature you control enters, you may draw a card if its power is greater than each other creature's power.

Until end of turn, target creature gets +X/+X and can only be blocked by X or more creatures.

Enchant land
Whenever enchanted land is tapped for mana, its controller adds {G}.
{G}, Sacrifice Sleeping Dryads: Draw a card.

When Hand of Fury enters, it gets +2/+2 and gains haste until end of turn.
At the beginning of your upkeep, if your fealty to Mountains is five or greater, transform Hand of Fury. (Each Mountain you control counts towards your fealty to Mountains.)

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.

Lifelink
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Spoiled Oracle mentors a creature, that creature gains lifelink until end of turn.

Primal {2}{R}{R} (During your turn, you may cast this spell for {2}{R}{R} instead of playing a land.)
Flying, prowess
At the beginning of your end step, if you didn't cast a spell this turn, sacrifice Thunderstride.

Whenever Roaring Illusion attacks alone, for each other creature you control, create a token that's a copy of that creature and that's tapped and attacking. Exile those tokens at the beginning of the next end step.

Whenever one or more creatures you control deal combat damage to a player, that player discards a card. Then that player may discard another card. If they don't, create two 2/1 black Nightmare creature tokens with “This creature can't block.”
Fleeting {1}{B}{B} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

Reach, trample
Revive {4}{G} ({4}{G}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Flying

You may reveal a creature card you own from outside the game and put it into your hand.
The next spell you cast this turn may be cast as though it had flash. Exile Impromptu Escapade.

When Signet Ring enters, scry 1.
{2}, {T}, Sacrifice Signet Ring: Add two mana of different colors.

Choose one —
• Target creature gets +3/+3 until end of turn.
• Target creature blocks this turn if able.
• Scry 1, then draw a card.

Equipped creature gets +2/+2.
Whenever equipped creature deals combat damage to a player, exile cards from the top of their library until they exile a nonland card. You may cast that card without paying its mana cost.
Equip {2}

When Ward-Lost Hermit enters, mill three cards.
{2}, {T}, Sacrifice Ward-Lost Hermit: Return target instant or sorcery card from your graveyard to your hand.

Whenever Battle-Scarred Combatant attacks or blocks, put a -1/-1 counter on it.

Recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)
Target creature you control fights target creature you don't control.

Flying, haste
Miyoga Firebird attacks each combat if able.
Whenever you cast your third instant or sorcery spell this turn, you may return Miyoga Firebird from your graveyard to the battlefield.