msem-instigator

Trample
Frontier Hoof gets +1/+1 for each other Centaur you control.

If you would lose unspent mana, that mana becomes colorless instead.

Trample

Flash
When Frontier Paragon enters, untap all creatures you control.

When Frontier Scouts enters, reveal the top card of your library. If it's a land, put it onto the battlefield tapped.

Enchant creature
Enchanted creature can't become untapped.
{4}{U}: Return Frozen Halo and enchanted creature to their owners' hands.

Catalyze. (The next spell you cast this turn costs {1} less to cast.)
Fueled Flame deals damage to any target equal to the number of times you've catalyzed this turn.

Enchant creature
Enchanted creature gets +2/+3 and has trample.

Choose one —
• Return all tapped creatures to their owners' hands.
• Return all untapped creatures to their owners' hands.

Enchant creature
Enchanted creature gets +2/+2 and attacks each combat if able.

Take an extra turn after this one. At the beginning of that turn's end step, sacrifice each land you control. Whenever you cast a spell during that turn, copy it. You may choose new targets for the copy.
Exile Futuretheft.

Trample
Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)

Equipped creature has haste.
Whenever equipped creature deals combat damage to a player, discard a card. If you do, draw a card.
Equip {1}

At the beginning of your upkeep, you win the game if the total mana value of permanents you control is exactly 21. If it's more than 21, sacrifice Gambling Table and all Card tokens you control. Otherwise, create a colorless Card artifact token with mana cost {2} and “{2}, Sacrifice this artifact: Draw a card.”

Flash

Vigilance
Death knell — Tap up to two creatures you don't control. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)

Choose flying, prowess, vigilance, or ward {2}. Create a colorless Equipment artifact token with “Equipped creature has the chosen ability” and equip {2}. (Then exile this card. You may cast the creature later from exile.)

When Gemcrusher Turtle enters, choose one —
• Destroy target artifact.
• Gemcrusher Turtle fights up to one target creature.

{T}: Add {C}.
{T}: Choose a color from among permanents you control. Add one mana of that color.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever Gentleman Thief deals combat damage to a player, gain control of target marked creature.

Target permanent phases out. (Then exile this card. You may cast the artifact later from exile.)

Ghastly Castle enters tapped unless another player controls a land that could produce {U} or {B}.
{T}: Add {U} or {B}.

Return target creature card from a graveyard to the battlefield under your control. Post a bounty on that creature. (Put a bounty counter on that creature. It has “When this creature dies, each opponent draws a card” as long as it has a bounty counter on it.)

Flying
When Ghastly Spirit enters, mill four cards, then return a nonland card from your graveyard to your hand.

Until end of turn, target creature you control gains “When this creature dies, return it to the battlefield under your control with a +1/+1 counter on it.”