Seething Pathblazer

Sacrifice an Elemental: Seething Pathblazer gets +2/+0 and gains first strike until end of turn.

Rebellion of the Flamekin

Whenever you clash, you may pay {1}. If you do, create a 3/1 red Elemental Shaman creature token. If you won, that token gains haste until end of turn. (This ability triggers after the clash ends.)

Flamekin Spitfire

{3}{R}: Flamekin Spitfire deals 1 damage to any target.

Smokebraider

{T}: Add two mana in any combination of colors. Spend this mana only to cast Elemental spells or activate abilities of Elementals.

Flamekin Brawler

{R}: Flamekin Brawler gets +1/+0 until end of turn.

Flamekin Bladewhirl

As an additional cost to cast this spell, reveal an Elemental card from your hand or pay {3}.

Incandescent Soulstoke

Other Elemental creatures you control get +1/+1.
{1}{R}, {T}: You may put an Elemental creature card from your hand onto the battlefield. That creature gains haste until end of turn. Sacrifice it at the beginning of the next end step.

Flamekin Harbinger

When Flamekin Harbinger enters, you may search your library for an Elemental card, reveal it, then shuffle and put that card on top.

Mountain

Flamekin Village

As Flamekin Village enters, you may reveal an Elemental card from your hand. If you don't, Flamekin Village enters tapped.
{T}: Add {R}.
{R}, {T}: Target creature gains haste until end of turn.

Ashling the Pilgrim

{1}{R}: Put a +1/+1 counter on Ashling the Pilgrim. If this is the third time this ability has resolved this turn, remove all +1/+1 counters from Ashling the Pilgrim, and it deals that much damage to each creature and each player.

Glarewielder

Haste
When Glarewielder enters, up to two target creatures can't block this turn.
Evoke {1}{R} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Brighthearth Banneret

Elemental spells and Warrior spells you cast cost {1} less to cast.
Reinforce 1—{1}{R} ({1}{R}, Discard this card: Put a +1/+1 counter on target creature.)