Overclocked Electromancer

At the beginning of combat on your turn, you may pay {E}{E}{E}. If you do, put a +1/+1 counter on Overclocked Electromancer.
Whenever Overclocked Electromancer attacks, double its power until end of turn.
Whenever Overclocked Electromancer deals combat damage to a creature, if that creature was dealt excess damage this turn, you get X {E}, where X is that excess damage.

Razorfield Ripper

Whenever Razorfield Ripper or equipped creature attacks, you get {E} (an energy counter), then it gets +X/+X until end of turn, where X is the amount of {E} you have.
Reconfigure—Pay {2} or {E}{E}{E}. (Pay {2} or {E}{E}{E}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Orderly Plaza

Orderly Plaza enters tapped.
{T}: Add {W} or {U}.

Suppression Ray

Tap all creatures target player controls. You may pay any amount of {E}. If you do, choose up to that many creatures tapped this way. Put a stun counter on each of them. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Suppression Ray // Orderly Plaza

Tempest Harvester

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

Smelted Chargebug

Menace
When Smelted Chargebug enters, you get {E}{E} (two energy counters).
Whenever Smelted Chargebug attacks, you may pay {E}. If you do, another target attacking creature gets +1/+0 and gains menace until end of turn.

Floodfarm Verge

{T}: Add {W}.
{T}: Add {U}. Activate only if you control a Plains or an Island.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

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.

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.

Boros Charm

Choose one —
• Boros Charm deals 4 damage to target player or planeswalker.
• Permanents you control gain indestructible until end of turn.
• Target creature gains double strike until end of turn.

Metastatic Evangel

Whenever another nontoken creature you control enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Deserted Beach

Deserted Beach enters tapped unless you control two or more other lands.
{T}: Add {W} or {U}.

Solar Transformer

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

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Volatile Stormdrake

Flying, hexproof from activated and triggered abilities
When Volatile Stormdrake enters, exchange control of Volatile Stormdrake and target creature an opponent controls. If you do, you get {E}{E}{E}{E}, then sacrifice that creature unless you pay an amount of {E} equal to its mana value.

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.

Zinnia, Valley's Voice

Flying
Zinnia, Valley's Voice gets +X/+0, where X is the number of other creatures you control with base power 1.
Creature spells you cast have offspring {2}. (You may pay an additional {2} as you cast a creature spell. If you do, when that creature enters, create a 1/1 token copy of it.)

Training Center

Training Center enters tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Raugrin Triome

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

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.

Lightning Runner

Double strike, haste
Whenever Lightning Runner 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.

Talisman of Progress

{T}: Add {C}.
{T}: Add {W} or {U}. Talisman of Progress deals 1 damage to you.

Emissary of Soulfire

When Emissary of Soulfire 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.)

Glimmer of Genius

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

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.

Spectator Seating

Spectator Seating enters tapped unless you have two or more opponents.
{T}: Add {R} or {W}.

Talisman of Creativity

{T}: Add {C}.
{T}: Add {U} or {R}. Talisman of Creativity deals 1 damage to you.

Mountain

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Consulate Surveillance

When Consulate Surveillance 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.

Displacer Kitten

Avoidance — Whenever you cast a noncreature spell, exile up to one target nonland permanent you control, then return that card to the battlefield under its owner's control.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Aether Swooper

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

Mondrak, Glory Dominus

If one or more tokens would be created under your control, twice that many of those tokens are created instead.
{1}{W/P}{W/P}, Sacrifice two other artifacts and/or creatures: Put an indestructible counter on Mondrak, Glory Dominus. ({W/P} can be paid with either {W} or 2 life.)

Blasphemous Act

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

Austere Command

Choose two —
• Destroy all artifacts.
• Destroy all enchantments.
• Destroy all creatures with mana value 3 or less.
• Destroy all creatures with mana value 4 or greater.

Lae'zel, Vlaakith's Champion

If you would put one or more counters on a creature or planeswalker you control or on yourself, put that many plus one of each of those kinds of counters on that permanent or player instead.
Choose a Background (You can have a Background as a second commander.)

Dreamtide Whale

Vanishing 2 (This creature enters with two time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Whenever a player casts their second spell each turn, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Riddle Gate Gargoyle

Flying
When Riddle Gate Gargoyle 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.

Agate Instigator

Offspring {1}{R} (You may pay an additional {1}{R} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Whenever another creature you control enters, this creature deals 1 damage to each opponent.

Aether Revolt

Revolt — As long as a permanent you controlled left the battlefield this turn, if a source you control would deal noncombat damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.
Whenever you get one or more {E}, Aether Revolt deals that much damage to any target.

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. Talisman of Conviction deals 1 damage to you.

Hallowed Fountain

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

Mentor of the Meek

Whenever another creature you control with power 2 or less enters, you may pay {1}. If you do, draw a card.

Moonshaker Cavalry

Flying
When Moonshaker Cavalry enters, creatures you control gain flying and get +X/+X until end of turn, where X is the number of creatures you control.

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.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

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.)

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Sundown Pass

Sundown Pass enters tapped unless you control two or more other lands.
{T}: Add {R} or {W}.

Plains

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Anointed Procession

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Amped Raptor

First strike
When Amped Raptor 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.

HELIOS One

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

Roil Cartographer

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

Stormcarved Coast

Stormcarved Coast enters tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Sea of Clouds

Sea of Clouds enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Aether Hub

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

Steam Vents

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

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Unstable Amulet

When Unstable Amulet enters, you get {E}{E} (two energy counters).
Whenever you cast a spell from anywhere other than your hand, Unstable Amulet deals 1 damage to each opponent.
{T}, Pay {E}{E}: Exile the top card of your library. You may play it until you exile another card with Unstable Amulet.

Conduit Goblin

When Conduit Goblin 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.

Arcane Signet

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

Sol Ring

Island

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.

Caretaker's Talent

(Gain the next level as a sorcery to add its ability.)
Whenever one or more tokens you control enter, draw a card. This ability triggers only once each turn.
{W}: Level 2
When this Class becomes level 2, create a token that's a copy of target token you control.
{3}{W}: Level 3
Creature tokens you control get +2/+2.

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.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Flawless Maneuver

If you control a commander, you may cast this spell without paying its mana cost.
Creatures you control gain indestructible until end of turn.

Delney, Streetwise Lookout

Creatures you control with power 2 or less can't be blocked by creatures with power 3 or greater.
If an ability of a creature you control with power 2 or less triggers, that ability triggers an additional time.

Whirler Virtuoso

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

Aethertorch Renegade

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

Crackling Falls

Crackling Falls enters tapped.
{T}: Add {U} or {R}.

Rush of Inspiration

Draw two cards. Then discard a card at random unless you pay {E}{E} (two energy counters).

Rush of Inspiration // Crackling Falls

Conversion Apparatus

{T}: Add {C}.
{3}, {T}: You get {E}{E}{E} (three energy counters).
{T}, Pay {E}{E}{E}: Add three mana in any combination of colors.

Command Tower

Tune the Narrative

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

Scurry of Gremlins

When Scurry of Gremlins enters, create two 1/1 red Gremlin creature tokens. Then you get an amount of {E} (energy counters) equal to the number of creatures you control.
Pay {E}{E}{E}{E}: Creatures you control get +1/+0 and gain haste until end of turn.

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.

Stroke of Midnight

Destroy target nonland permanent. Its controller creates a 1/1 white Human creature token.

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.

Eddytrail Hawk

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

Liberty Prime, Recharged

Vigilance, trample, haste
Whenever Liberty Prime, Recharged 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.

Sacred Foundry

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