Heartfire Hero

Valiant — Whenever this creature becomes the target of a spell or ability you control for the first time each turn, put a +1/+1 counter on it.
When this creature dies, it deals damage equal to its power to each opponent.

Clifftop Retreat

This land enters tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

Defiant Strike

Target creature gets +1/+0 until end of turn.
Draw a card.

Tenth District Legionnaire

Haste
Whenever you cast a spell that targets this creature, put a +1/+1 counter on this creature, then scry 1.

Mountain

Feather, the Redeemed

Flying
Whenever you cast an instant or sorcery spell that targets a creature you control, exile that card instead of putting it into your graveyard as it resolves. If you do, return it to your hand at the beginning of the next end step.

Plains

Monastery Mentor

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast a noncreature spell, create a 1/1 white Monk creature token with prowess.

Monstrous Rage

Target creature gets +2/+0 until end of turn. Create a Monster Role token attached to it. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has trample.)

Borrowed Hostility

Escalate {3} (Pay this cost for each mode chosen beyond the first.)
Choose one or both —
• Target creature gets +3/+0 until end of turn.
• Target creature gains first strike until end of turn.

Monastery Swiftspear

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Divine Resilience

Kicker {2}{W} (You may pay an additional {2}{W} as you cast this spell.)
Target creature you control gains indestructible until end of turn. If this spell was kicked, instead any number of target creatures you control gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

Sacred Foundry

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

Emberheart Challenger

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Valiant — Whenever this creature becomes the target of a spell or ability you control for the first time each turn, exile the top card of your library. Until end of turn, you may play that card.

Reckless Rage

Reckless Rage deals 4 damage to target creature you don't control and 2 damage to target creature you control.