Voltaic Brawler

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

Lathnu Hellion

Haste
When Lathnu Hellion enters, you get {E}{E} (two energy counters).
At the beginning of your end step, sacrifice Lathnu Hellion unless you pay {E}{E}.

Forest

Relic of Progenitus

{T}: Target player exiles a card from their graveyard.
{1}, Exile Relic of Progenitus: Exile all graveyards. Draw a card.

Sulfurous Springs

{T}: Add {C}.
{T}: Add {B} or {R}. Sulfurous Springs deals 1 damage to you.

Rush of Vitality

Target creature gets +1/+0 and gains lifelink and indestructible until end of turn. (Damage dealt by that creature also causes its controller to gain that much life, and it can't be destroyed by damage or effects that say "destroy.")

Aether Hub

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

Highspire Infusion

Target creature gets +3/+3 until end of turn. You get {E}{E} (two energy counters).

Llanowar Wastes

{T}: Add {C}.
{T}: Add {B} or {G}. Llanowar Wastes deals 1 damage to you.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Swamp

Gonti's Machinations

Whenever you lose life for the first time each turn, you get {E}. (You get an energy counter. Damage causes loss of life.)
Pay {E}{E}, Sacrifice Gonti's Machinations: Each opponent loses 3 life. You gain life equal to the life lost this way.

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).

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Terminate

Destroy target creature. It can't be regenerated.

Greenbelt Rampager

When Greenbelt Rampager enters, pay {E}{E} (two energy counters). If you can't, return Greenbelt Rampager to its owner's hand and you get {E}.

Live Fast

You draw two cards, lose 2 life, and get {E}{E} (two energy counters).

Glint-Sleeve Siphoner

Menace
Whenever Glint-Sleeve Siphoner enters or attacks, you get {E} (an energy counter).
At the beginning of your upkeep, you may pay {E}{E}. If you do, you draw a card and you lose 1 life.

Mountain

Karplusan Forest

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

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.