Attune with Aether

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. You get {E}{E} (two energy counters).

Colossus

Target creature gets +4/+2 and gains trample until end of turn.

Collision

Collision deals 6 damage to target creature with flying.

Collision // Colossus

Rootbound Crag

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

Game Trail

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

Aether Hub

When this land enters, you get {E} (an energy counter).
{T}: Add {C}.
{T}, Pay {E}: Add one mana of any color.

Longtusk Cub

Whenever this creature deals combat damage to a player, you get {E}{E} (two energy counters).
Pay {E}{E}: Put a +1/+1 counter on this creature.

Become Immense

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Target creature gets +6/+6 until end of turn.

Electrostatic Pummeler

When this creature enters, you get {E}{E}{E} (three energy counters).
Pay {E}{E}{E}: This creature gets +X/+X until end of turn, where X is its power.

Mountain

Forest

Blossoming Defense

Target creature you control gets +2/+2 and gains hexproof until end of turn.

Voltaic Brawler

When this creature enters, you get {E}{E} (two energy counters).
Whenever this creature attacks, you may pay {E}. If you do, it gets +1/+1 and gains trample until end of turn.

Harnessed Lightning

Choose target creature. You get {E}{E}{E} (three energy counters), then you may pay any amount of {E}. Harnessed Lightning deals that much damage to that creature.

Stomping Ground

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

Bristling Hydra

When this creature enters, you get {E}{E}{E} (three energy counters).
Pay {E}{E}{E}: Put a +1/+1 counter on this creature. It gains hexproof until end of turn.

Temur Battle Rage

Target creature gains double strike until end of turn.
Ferocious — That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Once Upon a Time

If this spell is the first spell you've cast this game, you may cast it without paying its mana cost.
Look at the top five cards of your library. You may reveal a creature or land card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Ghor-Clan Rampager

Trample
Bloodrush — {R}{G}, Discard this card: Target attacking creature gets +4/+4 and gains trample until end of turn.