msem-instigator

At the beginning of your end step, draw a card.
Whenever a creature deals combat damage to you, that creature's controller gains control of Ambition's Crown.

Flying, trample
When Ashen Persecutor enters the battlefield, target opponent reveals their hand. You choose a nonland card from it. That player discards that card and you gain life equal to its mana value.

Cast this spell only if an opponent controls two or more nonwhite creatures or you control six or more lands.
Create X 1/1 white Bird creature tokens with flying. You gain X life.

Elrayin, the Manaroot enters the battlefield tapped.
Whenever you tap another land for mana, put a creation counter on Elrayin.
{T}, Remove ten creation counters from Elrayin and sacrifice it: Untap all lands target player controls.

Flying, haste
Whenever Emissary of Antiquity deals combat damage to a player, you may cast an instant or sorcery spell with mana value 3 or less from your hand without paying its mana cost.

Kicker {X} (You may pay an additional {X} as you cast this spell.)
When Korrinary Warcaller enters the battlefield, if it was kicked, search your library for a Rebel permanent card with mana value X or less, put it onto the battlefield, then shuffle.

Whenever Merciless Shieldbreaker enters the battlefield or attacks, target opponent puts three rust counters on a permanent they control with no rust counters on it. That permanent gains “At the beginning of your upkeep, remove a rust counter from this permanent. Then if there are no rust counters on this permanent, sacrifice it and it deals 4 damage to you.”

Prismatic Cavern enters the battlefield tapped.
When Prismatic Cavern enters the battlefield, return a land you control to its owner's hand.
{T}: Add {C} and one mana of any color.

{1}, {T}: Exile target card from a graveyard. Scry 1.
{T}, Exile Soul Gate: Exile all graveyards.

{T}: Add {C}.
{2}, {T}: Draw a card. Activate only if you have no cards in hand.