Mountain

Sephiroth, One-Winged Angel

Flying
Super Nova — As this creature transforms into Sephiroth, One-Winged Angel, you get an emblem with "Whenever a creature dies, target opponent loses 1 life and you gain 1 life."
Whenever Sephiroth attacks, you may sacrifice any number of other creatures. If you do, draw that many cards.

Sephiroth, Fabled SOLDIER

Whenever Sephiroth enters or attacks, you may sacrifice another creature. If you do, draw a card.
Whenever another creature dies, target opponent loses 1 life and you gain 1 life. If this is the fourth time this ability has resolved this turn, transform Sephiroth.

Sephiroth, Fabled SOLDIER // Sephiroth, One-Winged Angel

Windcrag Siege

As this enchantment enters, choose Mardu or Jeskai.
• Mardu — If a creature attacking causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
• Jeskai — At the beginning of your upkeep, create a 1/1 red Goblin creature token. It gains lifelink and haste until end of turn.

Dalkovan Packbeasts

Vigilance
Mobilize 3 (Whenever this creature attacks, create three tapped and attacking 1/1 red Warrior creature tokens. Sacrifice them at the beginning of the next end step.)

Arabella, Abandoned Doll

Whenever Arabella attacks, it deals X damage to each opponent and you gain X life, where X is the number of creatures you control with power 2 or less.

Lightstall Inquisitor

Vigilance
When this creature enters, each opponent exiles a card from their hand and may play that card for as long as it remains exiled. Each spell cast this way costs {1} more to cast. Each land played this way enters tapped.

Starting Town

This land enters tapped unless it's your first, second, or third turn of the game.
{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color.

Summon: Brynhildr

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Chain — Exile the top card of your library. During any turn you put a lore counter on this Saga, you may play that card.
II, III — Gestalt Mode — When you next cast a creature spell this turn, it gains haste until end of turn.

Voice of Victory

Mobilize 2 (Whenever this creature attacks, create two tapped and attacking 1/1 red Warrior creature tokens. Sacrifice them at the beginning of the next end step.)
Your opponents can't cast spells during your turn.

Stadium Headliner

Mobilize 1 (Whenever this creature attacks, create a tapped and attacking 1/1 red Warrior creature token. Sacrifice it at the beginning of the next end step.)
{1}{R}, Sacrifice this creature: It deals damage equal to the number of creatures you control to target creature.

Sheltered by Ghosts

Enchant creature you control
When this Aura enters, exile target nonland permanent an opponent controls until this Aura leaves the battlefield.
Enchanted creature gets +1/+0 and has lifelink and ward {2}.

Sunbillow Verge

{T}: Add {W}.
{T}: Add {R}. Activate only if you control a Mountain or a Plains.

Plains

Multiversal Passage

As this land enters, choose a basic land type. Then you may pay 2 life. If you don't, it enters tapped.
This land is the chosen type.

Sacred Foundry

({T}: Add {R} or {W}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Get Lost

Destroy target creature, enchantment, or planeswalker. Its controller creates two Map tokens. (They're artifacts with "{1}, {T}, Sacrifice this token: Target creature you control explores. Activate only as a sorcery.")