(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Mill five cards.
II — Return all land cards from your graveyard to the battlefield tapped.
III — Until end of turn, another target creature you control gains trample and gets +X/+X, where X is the number of lands you control.
Reach, trample

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Target creature gets +5/+5 and gains shroud until end of turn. (It can't be the target of spells or abilities.)

Search your library and graveyard for up to four creature cards with different names that each have mana value X or less and reveal them. An opponent chooses two of those cards. Shuffle the chosen cards into your library and put the rest onto the battlefield. Exile Ecological Appreciation.

: Add .
, : Until end of turn, creatures your opponents control lose hexproof and shroud and can't have hexproof or shroud.

, : Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

When Proft's Eidetic Memory enters, draw a card.
You have no maximum hand size.
At the beginning of combat on your turn, if you've drawn more than one card this turn, put X +1/+1 counters on target creature you control, where X is the number of cards you've drawn this turn minus one.

As this enchantment enters, choose a creature type.
All creatures of the chosen type get -1/-1.

Players have no maximum hand size.
How Civil of You — At the beginning of your end step, each player may draw a card. Each opponent who does can't attack you or permanents you control during their next turn.

Exile any number of target creatures you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

: Add one mana of any color.
: Target creature becomes the color or colors of your choice until end of turn.

Whenever you cast a Myr spell, create a 1/1 colorless Myr artifact creature token.
At the beginning of combat on your turn, untap each Myr you control.
, : Put three +1/+1 counters on each Myr you control. Activate only during your turn.

Each noncreature artifact loses all abilities and becomes an artifact creature with power and toughness each equal to its mana value. If this enchantment leaves the battlefield, this effect continues until end of turn.

At the beginning of your end step, if this creature didn't attack this turn, it deals 2 damage to you unless it came under your control this turn.

Nicol Bolas has all loyalty abilities of all other planeswalkers on the battlefield.
+1: You draw a card. Each opponent exiles a card from their hand or a permanent they control.
−3: Destroy target creature or planeswalker.
−8: Each opponent who doesn't control a legendary creature or planeswalker loses the game.

At the beginning of your upkeep, you draw a card and you lose 1 life.

The first spell you cast from exile each turn has cascade. (When you cast your first spell from exile, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Whenever this creature enters or transforms into Brigid, Clachan's Heart, create a 1/1 green and white Kithkin creature token.
At the beginning of your first main phase, you may pay . If you do, transform Brigid.

Creatures you control get +1/+1.
Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Myriad
The "legend rule" doesn't apply to creature tokens you control.
Triggered abilities you control can't cause you to sacrifice or exile creature tokens you control.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for or one mana of that creature's color.)
Search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.