Jaya's Immolating Inferno

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.)
Jaya's Immolating Inferno deals X damage to each of up to three targets.

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.")

Sol Ring

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.

Crystalline Giant

At the beginning of combat on your turn, choose a kind of counter at random that Crystalline Giant doesn't have on it from among flying, first strike, deathtouch, hexproof, lifelink, menace, reach, trample, vigilance, and +1/+1. Put a counter of that kind on Crystalline Giant.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Invasion of the Giants

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Scry 2.
II — Draw a card. Then you may reveal a Giant card from your hand. When you do, Invasion of the Giants deals 2 damage to target opponent or planeswalker.
III — The next Giant spell you cast this turn costs {2} less to cast.

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.

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.

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.

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}

Sunrise Sovereign

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

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.

Fiery Emancipation

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

Squash

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

Goblin Electromancer

Instant and sorcery spells you cast cost {1} less to cast.

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.

Blasphemous Act

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

Stomp

Damage can't be prevented this turn. Stomp deals 2 damage to any target.

Bonecrusher Giant

Whenever Bonecrusher Giant becomes the target of a spell, Bonecrusher Giant deals 2 damage to that spell's controller.

Bonecrusher Giant // Stomp

Arcane Signet

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

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.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Stinkdrinker Daredevil

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

Sky Diamond

Crush Underfoot

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

Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.