Blaster Hulk

This spell costs {1} less to cast for each {E} (energy counter) you've paid or lost this turn.
Haste
Whenever this creature attacks, you get {E}{E}, then you may pay eight {E}. When you do, this creature deals 8 damage divided as you choose among up to eight targets.

Hightide Hermit

Defender
When this creature enters, you get {E}{E}{E}{E} (four energy counters).
Pay {E}{E}: This creature can attack this turn as though it didn't have defender.

Island

Iron Man, Titan of Innovation

Flying, haste
Genius Industrialist — Whenever Iron Man attacks, create a Treasure token, then you may sacrifice a noncreature artifact. If you do, search your library for an artifact card with mana value equal to 1 plus the sacrificed artifact's mana value, put it onto the battlefield tapped, then shuffle.

Lightning Runner

Double strike, haste
Whenever this creature attacks, you get {E}{E} (two energy counters), then you may pay eight {E}. If you pay, untap all creatures you control, and after this phase, there is an additional combat phase.

Sol Ring

Wrath of the Skies

You get X {E} (energy counters), then you may pay any amount of {E}. Destroy each artifact, creature, and enchantment with mana value less than or equal to the amount of {E} paid this way.

Rex, Cyber-Hound

Whenever Rex deals combat damage to a player, they mill two cards and you get {E}{E} (two energy counters).
Pay {E}{E}: Choose target creature card in a graveyard. Exile it with a brain counter on it. Activate only as a sorcery.
Rex has all activated abilities of all cards in exile with brain counters on them.

Shipwreck Moray

When this creature enters, you get {E}{E}{E}{E} (four energy counters).
Pay {E}: This creature gets +2/-2 until end of turn.

Dynavolt Tower

Whenever you cast an instant or sorcery spell, you get {E}{E} (two energy counters).
{T}, Pay {E}{E}{E}{E}{E}: This artifact deals 3 damage to any target.

Tempest Harvester

When this creature enters, you get {E}{E} (two energy counters).
{T}, Pay {E}: Draw a card, then discard a card.

Guide of Souls

Whenever another creature you control enters, you gain 1 life and get {E} (an energy counter).
Whenever you attack, you may pay {E}{E}{E}. When you do, put two +1/+1 counters and a flying counter on target attacking creature. It becomes an Angel in addition to its other types.

Aether Theorist

When this creature enters, you get {E}{E}{E} (three energy counters).
{T}, Pay {E}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Confiscation Coup

Choose target artifact or creature. You get {E}{E}{E}{E} (four energy counters), then you may pay an amount of {E} equal to that permanent's mana value. If you do, gain control of it.

The Motherlode, Excavator

When The Motherlode enters, choose target opponent. You get an amount of {E} (energy counters) equal to the number of nonbasic lands that player controls.
Whenever The Motherlode attacks, you may pay {E}{E}{E}{E}. When you do, destroy target nonbasic land defending player controls, and creatures that player controls without flying can't block this turn.

Mountain

Synth Eradicator

Haste
Whenever this creature attacks, exile the top card of your library. You may get {E}{E} (two energy counters). If you don't, you may play that card this turn.
{T}, Pay {E}{E}{E}: This creature deals 3 damage to any target.

Riddle Gate Gargoyle

Flying
When this creature enters, you get {E}{E}{E} (three energy counters).
Whenever you attack, you may pay {E}{E}. When you do, target creature you control gains lifelink until end of turn.

Aether Inspector

Vigilance
When this creature enters, you get {E}{E} (two energy counters).
Whenever this creature attacks, you may pay {E}{E}. If you do, create a 1/1 colorless Servo artifact creature token.

Satya, Aetherflux Genius

Menace, haste
Whenever Satya attacks, create a tapped and attacking token that's a copy of up to one other target nontoken creature you control. You get {E}{E} (two energy counters). At the beginning of the next end step, sacrifice that token unless you pay an amount of {E} equal to its mana value.

HELIOS One

{T}: Add {C}.
{1}, {T}: You get {E} (an energy counter).
{3}, {T}, Pay X {E}, Sacrifice this land: Destroy target nonland permanent with mana value X. Activate only as a sorcery.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Dr. Madison Li

Whenever you cast an artifact spell, you get {E} (an energy counter).
{T}, Pay {E}: Target creature gets +1/+0 and gains trample and haste until end of turn.
{T}, Pay {E}{E}{E}: Draw a card.
{T}, Pay {E}{E}{E}{E}{E}: Return target artifact card from your graveyard to the battlefield tapped.

Decoction Module

Whenever a creature you control enters, you get {E} (an energy counter).
{4}, {T}: Return target creature you control to its owner's hand.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

Basilica Skullbomb

{1}, Sacrifice this artifact: Draw a card.
{2}{W}, Sacrifice this artifact: Target creature you control gets +2/+2 and gains flying until end of turn. Draw a card. Activate only as a sorcery.

Brotherhood Scribe

Metalcraft — {T}: You get {E} (an energy counter). Activate only if you control three or more artifacts.
Whenever you get one or more {E} during your turn, creatures you control get +1/+1 until end of turn.

Aethersquall Ancient

Flying
At the beginning of your upkeep, you get {E}{E}{E} (three energy counters).
Pay eight {E}: Return all other creatures to their owners' hands. Activate only as a sorcery.

Eddytrail Hawk

Flying
When this creature enters, you get {E}{E} (two energy counters).
Whenever this creature attacks, you may pay {E}. If you do, another target attacking creature gains flying until end of turn.

Cyclops Superconductor

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, you get {E}{E}{E} (three energy counters).
When this creature dies, you may pay {E}{E}{E}. When you do, this creature deals damage equal to its power to any target.

Conduit Goblin

When this creature enters, you get {E}{E} (two energy counters).
At the beginning of combat on your turn, you may pay {E}. If you do, another target creature you control gets +1/+0 and gains haste until end of turn.

Glassblower's Puzzleknot

When this artifact enters, scry 2, then you get {E}{E}. (You get two energy counters. To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)
{2}{U}, Sacrifice this artifact: Scry 2, then you get {E}{E}.

Amped Raptor

First strike
When this creature enters, you get {E}{E} (two energy counters). Then if you cast it from your hand, exile cards from the top of your library until you exile a nonland card. You may cast that card by paying an amount of {E} equal to its mana value rather than paying its mana cost.

Thriving Turtle

When this creature enters, you get {E}{E} (two energy counters).
Whenever this creature attacks, you may pay {E}{E}. If you do, put a +1/+1 counter on it.

Galvanic Discharge

Choose target creature or planeswalker. You get {E}{E}{E} (three energy counters), then you may pay any amount of {E}. Galvanic Discharge deals that much damage to that permanent.

Stone Idol Generator

Whenever a creature you control attacks, you get {E} (an energy counter).
{T}, Pay six {E}: Create a 6/12 colorless Construct artifact creature token with trample. Activate only as a sorcery.

Phyrexian Ironworks

Whenever you attack, you get {E} (an energy counter).
{T}, Pay {E}{E}{E}: Create a 3/3 colorless Phyrexian Golem artifact creature token. Activate only as a sorcery.

Liberty Prime, Recharged

Vigilance, trample, haste
Whenever Liberty Prime attacks or blocks, sacrifice it unless you pay {E}{E} (two energy counters).
{2}, {T}, Sacrifice an artifact: You get {E}{E} and draw a card.

Deadlock Trap

This artifact enters tapped.
When this artifact enters, you get {E}{E} (two energy counters).
{T}, Pay {E}: Tap target creature or planeswalker. Its activated abilities can't be activated this turn.

Solstice Zealot

When this creature enters, you get {E}{E} (two energy counters).
{T}, Pay {E}: Tap target creature.

Aether Refinery

If you would get one or more {E} (energy counters), you get twice that many {E} instead.
{T}: You get {E}, then you may pay one or more {E}. If you do, create an X/X black Aetherborn creature token, where X is the amount of {E} paid this way.

Era of Innovation

Whenever an artifact or Artificer you control enters, you may pay {1}. If you do, you get {E}{E} (two energy counters).
Pay six {E}, Sacrifice Era of Innovation: Draw three cards.

Emissary of Soulfire

When this creature enters, you get {E}{E}{E} (three energy counters).
Pay {E}{E}: Put an exalted counter on target creature you control. Activate only as a sorcery. (Whenever a creature you control attacks alone, it gets +1/+1 until end of turn for each instance of exalted among permanents you control.)

Wheel of Potential

You get {E}{E}{E} (three energy counters), then you may pay any amount of {E}.
Each player may exile their hand and draw a number of cards equal to the amount of {E} paid this way. If seven or more {E} was paid this way, you may play cards you own exiled this way until the end of your next turn.

Aetherworks Marvel

Whenever a permanent you control is put into a graveyard, you get {E} (an energy counter).
{T}, Pay six {E}: Look at the top six cards of your library. You may cast a spell from among them without paying its mana cost. Put the rest on the bottom of your library in a random order.

Inventor's Axe

Flash
When this Equipment enters, you get {E}{E} (two energy counters).
When this Equipment enters, attach it to target creature you control.
Equipped creature gets +2/+0.
Equip—Pay {E}{E}.

Aetherstorm Roc

Flying
Whenever this creature or another creature you control enters, you get {E} (an energy counter).
Whenever this creature attacks, you may pay {E}{E}. If you do, put a +1/+1 counter on it and tap up to one target creature defending player controls.

Bespoke Battlewagon

{T}: You get {E}{E} (two energy counters).
{T}, Pay {E}{E}: Tap target creature.
{T}, Pay {E}{E}{E}: Draw a card.
Pay {E}{E}{E}{E}: This Vehicle becomes an artifact creature until end of turn.
Crew 4

Aether Hub

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

Inspired Inventor

When this creature enters, choose one —
• You get {E}{E}{E} (three energy counters).
• Put a +1/+1 counter on target creature.
• Create a 1/1 colorless Servo artifact creature token.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Aether Spike

Choose target spell. You get {E}{E} (two energy counters), then you may pay any amount of {E}. Counter that spell unless its controller pays {1} for each {E} paid this way.

Whirler Virtuoso

When this creature enters, you get {E}{E}{E} (three energy counters).
Pay {E}{E}{E}: Create a 1/1 colorless Thopter artifact creature token with flying.

Automated Assembly Line

Whenever one or more artifact creatures you control deal combat damage to a player, you get {E} (an energy counter).
Pay {E}{E}{E}: Create a tapped 3/3 colorless Robot artifact creature token.

Assaultron Dominator

When this creature enters, you get {E}{E} (two energy counters).
Whenever an artifact creature you control attacks, you may pay {E}. If you do, put your choice of a +1/+1, first strike, or trample counter on that creature.

Localized Destruction

You get {E} (an energy counter), then you may pay one or more {E}. If you do, each creature you control with power equal to the amount of {E} paid this way gains indestructible until end of turn.
Destroy all creatures.

Izzet Generatorium

If you would get one or more {E} (energy counters), you get that many plus one {E} instead.
{T}: Draw a card. Activate only if you've paid or lost four or more {E} this turn.

Territorial Gorger

Trample
Whenever you get one or more {E} (energy counters), this creature gets +2/+2 until end of turn.

Aether Chaser

First strike
When this creature enters, you get {E}{E} (two energy counters).
Whenever this creature attacks, you may pay {E}{E}. If you do, create a 1/1 colorless Servo artifact creature token.

Filigree Attendant

Flying
Filigree Attendant's power is equal to the number of artifacts you control.

Solar Transformer

This artifact enters tapped.
When this artifact enters, you get {E}{E}{E} (three energy counters).
{T}: Add {C}.
{T}, Pay {E}: Add one mana of any color.

Consul's Shieldguard

When this creature enters, you get {E}{E} (two energy counters).
Whenever this creature attacks, you may pay {E}. If you do, another target attacking creature gains indestructible until end of turn.

Plains

Consulate Turret

{T}: You get {E} (an energy counter).
{T}, Pay {E}{E}{E}: This artifact deals 2 damage to target player or planeswalker.

T-45 Power Armor

When this Equipment enters, you get {E}{E} (two energy counters).
Equipped creature gets +3/+3 and doesn't untap during its controller's untap step.
At the beginning of your upkeep, you may pay {E}. If you do, untap equipped creature, then put your choice of a menace, trample, or lifelink counter on it.
Equip {3}

Roil Cartographer

Landfall — Whenever a land you control enters, you get {E} (an energy counter).
{T}, Pay six {E}: Draw three cards.

Command Tower

Aethersphere Harvester

Flying
When this Vehicle enters, you get {E}{E} (two energy counters).
Pay {E}: This Vehicle gains lifelink until end of turn.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Fabrication Module

Whenever you get one or more {E} (energy counters), put a +1/+1 counter on target creature you control.
{4}, {T}: You get {E}.

Aethertorch Renegade

When this creature enters, you get {E}{E}{E}{E} (four energy counters).
{T}, Pay {E}{E}: This creature deals 1 damage to target creature.
{T}, Pay eight {E}: This creature deals 6 damage to target player or planeswalker.

Tune the Narrative

Draw a card. You get {E}{E} (two energy counters).

Sai, Master Thopterist

Whenever you cast an artifact spell, create a 1/1 colorless Thopter artifact creature token with flying.
{1}{U}, Sacrifice two artifacts: Draw a card.

Glimmer of Genius

Scry 2, then draw two cards. You get {E}{E} (two energy counters).

Static Prison

When this enchantment enters, exile target nonland permanent an opponent controls until this enchantment leaves the battlefield. You get {E}{E} (two energy counters).
At the beginning of your first main phase, sacrifice this enchantment unless you pay {E}.

Jolted Awake

Choose up to one target artifact or creature card in your graveyard. You get {E}{E} (two energy counters). Then you may pay an amount of {E} equal to that card's mana value. If you do, return it from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Vault 112: Sadistic Simulation

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Tap up to one target creature and put a stun counter on it. You get {E}{E} (two energy counters).
III — Pay any amount of {E}. If you paid one or more {E} this way, shuffle your library, then exile that many cards from the top. You may play one of those cards without paying its mana cost.

Aether Meltdown

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature or Vehicle
When this Aura enters, you get {E}{E} (two energy counters).
Enchanted creature gets -4/-0.

Consulate Surveillance

When this enchantment enters, you get {E}{E}{E}{E} (four energy counters).
Pay {E}{E}: Prevent all damage that would be dealt to you this turn by a source of your choice.

Salvation Colossus

Flying, vigilance, trample
Whenever you attack, other creatures you control get +2/+2 and gain indestructible until end of turn.
Unearth—Pay eight {E}. (Pay eight energy counters: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Electrosiphon

Counter target spell. You get an amount of {E} (energy counters) equal to its mana value.