Emergent Ultimatum

T, Pay 1 life, Sacrifice this land: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

Landfall — Whenever a land you control enters, investigate. (Create a Clue token. It's an artifact with "2, Sacrifice this token: Draw a card.") Whenever you sacrifice a Clue, put a +1/+1 counter on this creature.

As this creature enters, choose a color. All cards that aren't on the battlefield, spells, and permanents are the chosen color in addition to their other colors.

T: Add C. T: Draw a card. Activate only if you have exactly seven cards in hand.

As an additional cost to cast this spell, sacrifice a creature. Add an amount of B equal to the sacrificed creature's mana value.

Choose a creature type. For each creature you control of the chosen type, create a token that's a copy of that creature. Those tokens gain haste. Exile them at the beginning of the next end step.

Converge — Exile target nonland permanent if its mana value is less than or equal to the number of colors of mana spent to cast this spell.

You can't cast permanent spells. 4, T: Add WUBRG. When you next cast a spell this turn, exile cards from the top of your library until you exile an instant or sorcery card with lesser mana value. Until end of turn, you may cast that card without paying its mana cost. Put each other card exiled this way on the bottom of your library in a random order.