Game Trail

As Game Trail enters, you may reveal a Mountain or Forest card from your hand. If you don't, Game Trail enters tapped.
{T}: Add {R} or {G}.

Harness the Storm

Whenever you cast an instant or sorcery spell from your hand, you may cast target card with the same name as that spell from your graveyard. (You still pay its costs.)

Errant, Street Artist

Flash
Defender, haste
{1}{U}, {T}: Copy target spell you control that wasn't cast. You may choose new targets for the copy.

Copperline Gorge

Copperline Gorge enters tapped unless you control two or fewer other lands.
{T}: Add {R} or {G}.

Mountain

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

Ornithopter

Ketria Triome

({T}: Add {G}, {U}, or {R}.)
Ketria Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Ancestral Anger

Target creature gains trample and gets +X/+0 until end of turn, where X is 1 plus the number of cards named Ancestral Anger in your graveyard. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)
Draw a card.

Paradoxical Outcome

Return any number of target nonland, nontoken permanents you control to their owners' hands. Draw a card for each card returned to your hand this way.

Burning-Tree Emissary

When Burning-Tree Emissary enters, add {R}{G}.

Mox Amber

{T}: Add one mana of any color among legendary creatures and planeswalkers you control.

Venerated Rotpriest

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
Whenever a creature you control becomes the target of a spell, target opponent gets a poison counter.

Frostboil Snarl

As Frostboil Snarl enters, you may reveal an Island or Mountain card from your hand. If you don't, Frostboil Snarl enters tapped.
{T}: Add {U} or {R}.

Renegade Tactics

Target creature can't block this turn.
Draw a card.

Expedite

Target creature gains haste until end of turn.
Draw a card.

Shivan Reef

{T}: Add {C}.
{T}: Add {U} or {R}. Shivan Reef deals 1 damage to you.

Spark of Creativity

Choose target creature. Exile the top card of your library. You may have Spark of Creativity deal damage to that creature equal to the exiled card's mana value. If you don't, you may play that card until end of turn.

Harnfel, Horn of Bounty

Discard a card: Exile the top two cards of your library. You may play those cards this turn.

Birgi, God of Storytelling

Whenever you cast a spell, add {R}. Until end of turn, you don't lose this mana as steps and phases end.
Creatures you control can boast twice during each of your turns rather than once.