Oath of Lieges

At the beginning of each player's upkeep, that player chooses target player who controls more lands than they do and is their opponent. The first player may search their library for a basic land card, put that card onto the battlefield, then shuffle.

Plains

Treacherous Blessing

When Treacherous Blessing enters, draw three cards.
Whenever you cast a spell, you lose 1 life.
When Treacherous Blessing becomes the target of a spell or ability, sacrifice it.

Blacksmith's Skill

Target permanent gains hexproof and indestructible until end of turn. If it's an artifact creature, it gets +2/+2 until end of turn.

Clever Concealment

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Any number of target nonland permanents you control phase out. (Treat them and anything attached to them as though they don't exist until your next turn.)

Proft's Eidetic Memory

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.

Echo of Death's Wail

Flying, haste
When Echo of Death's Wail enters, gain control of all Rat tokens.
Whenever Echo of Death's Wail attacks, you may sacrifice another creature. If you do, draw a card.

Tribute to Horobi

(As this Saga enters and after your draw step, add a lore counter.)
I, II — Each opponent creates a 1/1 black Rat Rogue creature token.
III — Exile this Saga, then return it to the battlefield transformed under your control.

Tribute to Horobi // Echo of Death's Wail

Grim Guardian

Constellation — Whenever Grim Guardian or another enchantment you control enters, each opponent loses 1 life.

Spirited Companion

When Spirited Companion enters, draw a card.

Military Intelligence

Whenever you attack with two or more creatures, draw a card.

Chivalric Alliance

Whenever you attack with two or more creatures, draw a card.
{2}, Discard a card: Create a 2/2 white and blue Knight creature token with vigilance.

As Foretold

At the beginning of your upkeep, put a time counter on As Foretold.
Once each turn, you may pay {0} rather than pay the mana cost for a spell you cast with mana value X or less, where X is the number of time counters on As Foretold.

Black Market Connections

At the beginning of your first main phase, choose one or more —
• Sell Contraband — Create a Treasure token. You lose 1 life.
• Buy Information — Draw a card. You lose 2 life.
• Hire a Mercenary — Create a 3/2 colorless Shapeshifter creature token with changeling. You lose 3 life. (It has every creature type.)

Call of the Ring

At the beginning of your upkeep, the Ring tempts you.
Whenever you choose a creature as your Ring-bearer, you may pay 2 life. If you do, draw a card.

World-Weary

Enchant creature
Enchanted creature gets -4/-4.
Basic landcycling {1}{B} ({1}{B}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Flawless Maneuver

If you control a commander, you may cast this spell without paying its mana cost.
Creatures you control gain indestructible until end of turn.