Aether Vial

At the beginning of your upkeep, you may put a charge counter on Aether Vial.
{T}: You may put a creature card with mana value equal to the number of charge counters on Aether Vial from your hand onto the battlefield.

Call of the Herd

Create a 3/3 green Elephant creature token.
Flashback {3}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Challenger Troll

Each creature you control with power 4 or greater can't be blocked by more than one creature.

Chromatic Sphere

{1}, {T}, Sacrifice Chromatic Sphere: Add one mana of any color. Draw a card.

Elvish Harbinger

When Elvish Harbinger enters, you may search your library for an Elf card, reveal it, then shuffle and put that card on top.
{T}: Add one mana of any color.

Showdown of the Skalds

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Exile the top four cards of your library. Until the end of your next turn, you may play those cards.
II, III — Whenever you cast a spell this turn, put a +1/+1 counter on target creature you control.

Fierce Retribution

Cleave {5}{W} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)
Destroy target [attacking] creature.

Sunlit Marsh

({T}: Add {W} or {B}.)
Sunlit Marsh enters tapped.

Prizefight

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)
Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Garth One-Eye

{T}: Choose a card name that hasn't been chosen from among Disenchant, Braingeyser, Terror, Shivan Dragon, Regrowth, and Black Lotus. Create a copy of the card with the chosen name. You may cast the copy. (You still pay its costs.)

Spectral Procession

Create three 1/1 white Spirit creature tokens with flying.

Fyndhorn Elves

Bond of Discipline

Tap all creatures your opponents control. Creatures you control gain lifelink until end of turn.

Aesi, Tyrant of Gyre Strait

You may play an additional land on each of your turns.
Landfall — Whenever a land you control enters, you may draw a card.

Omenpath to Naya

Vanishing 4 (This land enters the battlefield with four time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
{T}: Add {R}, {G}, or {W}.

Plains

Yosei, the Morning Star

Flying
When Yosei, the Morning Star dies, target player skips their next untap step. Tap up to five target permanents that player controls.

Silverglade Pathfinder

{1}{G}, {T}, Discard a card: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Chatzuk, Mighty Guitarist

Banding (Just ask around until you find someone who knows.)
Creature spells you cast with banding cost {2} less to cast.
Whenever two or more creatures you control attack in a band, each creature in that band gets +1/+1 until end of turn for each creature in that band.

Cathar Commando

Flash (You may cast this spell any time you could cast an instant.)
{1}, Sacrifice this creature: Destroy target artifact or enchantment.

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Mirri's Guile

At the beginning of your upkeep, you may look at the top three cards of your library, then put them back in any order.

Planar Disruption

Enchant artifact, creature, or planeswalker
Enchanted permanent can't attack or block, and its activated abilities can't be activated.

Forest

Cleaver Blow

Multicleave {1} (You may pay an additional {1} any number of times as you cast this spell. For each time you do, choose a paired set of square brackets and remove the words in between.)
 Destroy target [nonblack] creature [with mana value 3 or less] [an opponent controls]. You [and its controller each] draw a card [and lose 2 life]. Create a [tapped] 1/1 white Spirit creature token with flying.

Phyrexian Missionary

Kicker {1}{B} (You may pay an additional {1}{B} as you cast this spell.)
Lifelink
When Phyrexian Missionary enters, if it was kicked, return target creature card from your graveyard to your hand.

Triumph of Ferocity

At the beginning of your upkeep, draw a card if you control the creature with the greatest power or tied for the greatest power.