Mountain

Nebula Dragon

Flying
When this creature enters, it deals 3 damage to any target.

Molten Exhale

You may cast this spell as though it had flash if you behold a Dragon as an additional cost to cast it. (To behold a Dragon, choose a Dragon you control or reveal a Dragon card from your hand.)
Molten Exhale deals 4 damage to target creature or planeswalker.

Meteor Golem

When this creature enters, destroy target nonland permanent an opponent controls.

Random Encounter

Shuffle your library, then mill four cards. Put each creature card milled this way onto the battlefield. They gain haste. At the beginning of the next end step, return those creatures to their owner's hand.
Flashback {6}{R}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Molten Man, Inferno Incarnate

When Molten Man enters, search your library for a basic Mountain card, put it onto the battlefield tapped, then shuffle.
Molten Man gets +1/+1 for each Mountain you control.
When Molten Man leaves the battlefield, sacrifice a land.

Ring of the Lucii

{T}: Add {C}{C}.
{2}, {T}, Pay 1 life: Tap target nonland permanent.

Zookeeper Mechan

{T}: Add {R}.
{6}{R}: Target creature you control gets +4/+0 until end of turn. Activate only as a sorcery.

Dragon Mage

Flying
Whenever this creature deals combat damage to a player, each player discards their hand, then draws seven cards.

Sunset Strikemaster

{T}: Add {R}.
{2}{R}, {T}, Sacrifice this creature: It deals 6 damage to target creature with flying.

Territorial Bruntar

Reach
Landfall — Whenever a land you control enters, exile cards from the top of your library until you exile a nonland card. You may cast that card this turn.

Carnelian Orb of Dragonkind

{T}: Add {R}. If that mana is spent on a Dragon creature spell, it gains haste until end of turn.