Arcane Signet

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

Tectonic Giant

Whenever Tectonic Giant attacks or becomes the target of a spell an opponent controls, choose one —
• Tectonic Giant deals 3 damage to each opponent.
• Exile the top two cards of your library. Choose one of them. Until the end of your next turn, you may play that card.

Maskwood Nexus

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Thundercloud Shaman

When Thundercloud Shaman enters, it deals damage equal to the number of Giants you control to each non-Giant creature.

Battle of Frost and Fire

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Battle of Frost and Fire deals 4 damage to each non-Giant creature and each planeswalker.
II — Scry 3.
III — Whenever you cast a spell with mana value 5 or greater this turn, draw two cards, then discard a card.

Aegar, the Freezing Flame

Whenever a creature or planeswalker an opponent controls is dealt excess damage, if a Giant, Wizard, or spell you controlled dealt damage to it this turn, draw a card.

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Bottle-Cap Blast

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Bottle-Cap Blast deals 5 damage to any target. If excess damage was dealt to a permanent this way, create that many tapped Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mountain

Wizard's Lightning

This spell costs {2} less to cast if you control a Wizard.
Wizard's Lightning deals 3 damage to any target.

Basalt Ravager

When Basalt Ravager enters, it deals X damage to any target, where X is the greatest number of creatures you control that have a creature type in common.

Stormcatch Mentor

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Instant and sorcery spells you cast cost {1} less to cast.

Volcanic Spite

Volcanic Spite deals 3 damage to target creature, planeswalker, or battle. You may put a card from your hand on the bottom of your library. If you do, draw a card.

Izzet Signet

Command Tower

Furnace Host Charger

Haste
Mountaincycling {2} ({2}, Discard this card: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.)

Cyclone Summoner

When Cyclone Summoner enters, if you cast it from your hand, return all permanents to their owners' hands except for Giants, Wizards, and lands.

Prophetic Titan

Delirium — When Prophetic Titan enters, choose one. If there are four or more card types among cards in your graveyard, choose both instead.
• Prophetic Titan deals 4 damage to any target.
• Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in a random order.

Comet Storm

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)
Choose any target, then choose another target for each time this spell was kicked. Comet Storm deals X damage to each of them.

Starstorm

Starstorm deals X damage to each creature.
Cycling {3} ({3}, Discard this card: Draw a card.)

Reliquary Tower

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

Temple of Epiphany

Temple of Epiphany enters tapped.
When Temple of Epiphany enters, scry 1.
{T}: Add {U} or {R}.

Stinkdrinker Daredevil

Giant spells you cast cost {2} less to cast.

Sol Ring

Talisman of Creativity

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

Sulfur Falls

Sulfur Falls enters tapped unless you control an Island or a Mountain.
{T}: Add {U} or {R}.

Glimpse the Cosmos

Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.
As long as you control a Giant, you may cast Glimpse the Cosmos from your graveyard by paying {U} rather than paying its mana cost. If you cast Glimpse the Cosmos this way and it would be put into your graveyard, exile it instead.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

City on Fire

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
If a source you control would deal damage to a permanent or player, it deals triple that damage instead.

Galvanic Iteration

When you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.
Flashback {1}{U}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Training Center

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

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Repercussion

Whenever a creature is dealt damage, Repercussion deals that much damage to that creature's controller.

Thryx, the Sudden Storm

Flash
Flying
Spells you cast with mana value 5 or greater cost {1} less to cast and can't be countered.

Calamity Bearer

If a Giant source you control would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Steam Vents

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

Mana Geyser

Add {R} for each tapped land your opponents control.

Magebane Armor

Equipped creature gets +2/+4 and loses flying.
Prevent all noncombat damage that would be dealt to equipped creature.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Squash

This spell costs {3} less to cast if you control a Giant.
Squash deals 6 damage to target creature or planeswalker.

Inferno Titan

{R}: Inferno Titan gets +1/+0 until end of turn.
Whenever Inferno Titan enters or attacks, it deals 3 damage divided as you choose among one, two, or three targets.

Hall of Storm Giants

If you control two or more other lands, Hall of Storm Giants enters tapped.
{T}: Add {U}.
{5}{U}: Until end of turn, Hall of Storm Giants becomes a 7/7 blue Giant creature with ward {3}. It's still a land. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)

Chandra's Ignition

Target creature you control deals damage equal to its power to each other creature and each opponent.

Ghostfire Slice

Devoid (This card has no color.)
This spell costs {2} less to cast if an opponent controls a multicolored permanent.
Ghostfire Slice deals 4 damage to any target.

Fall of the Hammer

Target creature you control deals damage equal to its power to another target creature.

Crush Underfoot

Choose a Giant creature you control. It deals damage equal to its power to target creature.

Sunrise Sovereign

Other Giant creatures you control get +2/+2 and have trample.

Irencrag Pyromancer

Whenever you draw your second card each turn, Irencrag Pyromancer deals 3 damage to any target.

Taurean Mauler

Changeling (This card is every creature type.)
Whenever an opponent casts a spell, you may put a +1/+1 counter on Taurean Mauler.

Warchief Giant

Haste
Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Thought Vessel

Herald's Horn

As Herald's Horn enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Quakebringer

Your opponents can't gain life.
At the beginning of your upkeep, Quakebringer deals 2 damage to each opponent. This ability triggers only if Quakebringer is on the battlefield or if Quakebringer is in your graveyard and you control a Giant.
Foretell {2}{R}{R}

Scorching Shot

Scorching Shot deals 5 damage to target creature.

Flame of Anor

Choose one. If you control a Wizard as you cast this spell, you may choose two instead.
• Target player draws two cards.
• Destroy target artifact.
• Flame of Anor deals 5 damage to target creature.

Prismari Command

Choose two —
• Prismari Command deals 2 damage to any target.
• Target player draws two cards, then discards two cards.
• Target player creates a Treasure token.
• Destroy target artifact.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Reflections of Littjara

As Reflections of Littjara enters, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Call Forth the Tempest

Cascade, cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order. Then do it again.)
Call Forth the Tempest deals damage to each creature your opponents control equal to the total mana value of other spells you've cast this turn.

Flame Slash

Flame Slash deals 4 damage to target creature.

Harmonic Prodigy

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
If an ability of a Shaman or another Wizard you control triggers, that ability triggers an additional time.

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Island

Blasphemous Act

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

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Surtr, Fiery Jötun

Trample (This creature can deal excess combat damage to the player it's attacking.)
Whenever you cast a historic spell, Surtr, Fiery Jötun deals 3 damage to any target. (Artifacts, legendaries, and Sagas are historic.)