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.

Boots of Speed

Equipped creature gets +1/+0 and has haste.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Crush Underfoot

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

Basalt Ravager

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

Squash

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

Cyclone Summoner

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

Rune of Speed

Enchant permanent
When Rune of Speed enters the battlefield, draw a card.
As long as enchanted permanent is a creature, it gets +1/+0 and has haste.
As long as enchanted permanent is an Equipment, it has "Equipped creature gets +1/+0 and has haste."

Giant's Grasp

Enchant Giant you control
When Giant's Grasp enters the battlefield, gain control of target nonland permanent for as long as Giant's Grasp remains on the battlefield.

Giant's Amulet

When Giant's Amulet enters the battlefield, you may pay {3}{U}. If you do, create a 4/4 blue Giant Wizard creature token, then attach Giant's Amulet to it.
Equipped creature gets +0/+1 and has "This creature has hexproof as long as it's untapped." (It can't be the target of spells or abilities your opponents control.)
Equip {2}

Rimeshield Frost Giant

Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.)

Reflections of Littjara

As Reflections of Littjara enters the battlefield, 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.)

Thundercloud Shaman

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

Rune of Flight

Enchant permanent
When Rune of Flight enters the battlefield, draw a card.
As long as enchanted permanent is a creature, it has flying.
As long as enchanted permanent is an Equipment, it has "Equipped creature has flying."

Surtland Elementalist

As an additional cost to cast this spell, reveal a Giant card from your hand or pay {2}.
Whenever Surtland Elementalist attacks, you may cast an instant or sorcery spell from your hand without paying its mana cost.

Hall of Storm Giants

If you control two or more other lands, Hall of Storm Giants enters the battlefield 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}.)

Shatterskull Charger

Kicker {2}
Trample, haste
If Shatterskull Charger was kicked, it enters the battlefield with a +1/+1 counter on it.
At the beginning of your end step, if Shatterskull Charger doesn't have a +1/+1 counter on it, return it to its owner's hand.

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

Borderland Behemoth

Trample
Borderland Behemoth gets +4/+4 for each other Giant you control.

Siegebreaker Giant

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
{3}{R}: Target creature can't block this turn.

Undersea Invader

Flash
Undersea Invader enters the battlefield tapped.

Sunrise Sovereign

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

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.

Critical Hit

Target creature gains double strike until end of turn.
When you roll a natural 20, return Critical Hit from your graveyard to your hand. (A natural 20 is a roll that displays 20 on the die.)

Cinderheart Giant

Trample
When Cinderheart Giant dies, it deals 7 damage to a creature an opponent controls chosen at random.

Stinkdrinker Daredevil

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

True Polymorph

Target artifact or creature becomes a copy of another target artifact or creature.

Littjara Kinseekers

Changeling (This card is every creature type.)
When Littjara Kinseekers enters the battlefield, if you control three or more creatures that share a creature type, put a +1/+1 counter on Littjara Kinseekers, then scry 1.

Greataxe

Equipped creature gets +4/+0.
Equip {5} ({5}: Attach to target creature you control. Equip only as a sorcery.)

Saw It Coming

Counter target spell.
Foretell {1}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Relentless Assault

Untap all creatures that attacked this turn. After this main phase, there is an additional combat phase followed by an additional main phase.

Zalto, Fire Giant Duke

Trample
Whenever Zalto, Fire Giant Duke is dealt damage, venture into the dungeon. (Enter the first room or advance to the next room.)

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.

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}

Stormcarved Coast

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

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.

Awaken the Ancient

Enchant Mountain
Enchanted Mountain is a 7/7 red Giant creature with haste. It's still a land.

Antagonize

Target creature gets +4/+3 until end of turn.

Frost Titan

Whenever Frost Titan becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {2}.
Whenever Frost Titan enters the battlefield or attacks, tap target permanent. It doesn't untap during its controller's next untap step.

Inferno Titan

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

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.

Two-Headed Giant

Whenever Two-Headed Giant attacks, flip two coins. If both coins come up heads, Two-Headed Giant gains double strike until end of turn. If both coins come up tails, Two-Headed Giant gains menace until end of turn.

Doomskar Titan

When Doomskar Titan enters the battlefield, creatures you control get +1/+0 and gain haste until end of turn.
Foretell {4}{R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Hamletback Goliath

Whenever another creature enters the battlefield, you may put X +1/+1 counters on Hamletback Goliath, where X is that creature's power.

Hearthcage Giant

When Hearthcage Giant enters the battlefield, create two 3/1 red Elemental Shaman creature tokens.
Sacrifice an Elemental: Target Giant creature gets +3/+1 until end of turn.