Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever a creature you control attacks alone, you may search your library for an Aura card that could enchant that creature, put it onto the battlefield attached to that creature, then shuffle.

Arixmethes enters tapped with five slumber counters on it.
As long as Arixmethes has a slumber counter on it, it's a land. (It's not a creature.)
Whenever you cast a spell, you may remove a slumber counter from Arixmethes.
: Add .

When this creature enters, each creature target opponent controls loses all abilities, becomes a Coward in addition to its other types, and has base power and toughness 1/1.

Equipped creature gets +1/+1.
Whenever equipped creature attacks, you get (two energy counters).
Pay : Choose target creature that's blocking equipped creature. Flip a coin. If you win the flip, exile the chosen creature. Otherwise, this Equipment deals 1 damage to it.
Equip

Casualty X. The copy isn't legendary and has starting loyalty X. (As you cast this spell, you may sacrifice a creature with power X. When you do, copy this spell. The copy becomes a token.)
+1: Each opponent loses 2 life unless they discard a card. If you control a Demon or Devil, you gain 2 life.
−2: Create a 1/1 red Devil creature token with "When this token dies, it deals 1 damage to any target."
−7: Target player draws seven cards and loses 7 life.

Flying
Whenever this creature enters or attacks, goad target creature. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)
Whenever a goaded creature attacks, it deals 1 damage to its controller.

+1: Chandra deals 2 damage to any target.
−2: Chandra deals 4 damage to target creature and 2 damage to that creature's controller.
−8: Chandra deals 10 damage to target player and each creature that player controls.

Enchant creature you control
Enchanted creature gets +2/+2 for each Aura and Equipment attached to it.
All damage that would be dealt to you is dealt to enchanted creature instead.

Flying
When Runo enters, put up to one target creature card from your graveyard on top of your library.
At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If a creature card with mana value 6 or greater is revealed this way, transform Runo.

Haste
Whenever Skullbriar deals combat damage to a player, put a +1/+1 counter on it.
Counters remain on Skullbriar as it moves to any zone other than a player's hand or library.

Enchant land
When enchanted land becomes tapped, destroy it. That land's controller may attach this Aura to a land of their choice.

Until end of turn, target creature gets +3/+3 and gains trample and "Whenever this creature deals combat damage to a player, draw that many cards."

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.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — You draw three cards and you lose 3 life.
II — Mill three cards.
III — Choose up to three target creature cards with total mana value 8 or less in your graveyard. Return each of them to the battlefield with a necrodermis counter on it. They're artifacts in addition to their other types.

Whenever an opponent casts a spell during your turn and when this creature dies, create a green and white Elemental creature token with "This token's power and toughness are each equal to the number of creatures you control."

Each other creature you control enters with a number of additional +1/+1 counters on it equal to this creature's power and as a Mutant in addition to its other types.

: This enchantment becomes an X/X Wall creature with defender in addition to its other types until end of turn.

Flying, lifelink
Battalion — Whenever Falcon and at least two other creatures attack, put a +1/+1 counter on him and scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Whenever a creature you control enters, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on the creature, then put the card back or put it into your graveyard.)

During your turn, each non-Equipment artifact and non-Aura enchantment you control with mana value 4 or greater is a 4/4 Elemental creature in addition to its other types and has indestructible, haste, and "Whenever this creature deals combat damage to a player, draw a card."