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.

Command Tower

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

Mountain

Slick Sequence

Slick Sequence deals 2 damage to any target. If you've cast another spell this turn, draw a card.

Ravenform

Exile target artifact or creature. Its controller creates a 1/1 blue Bird creature token with flying.
Foretell {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.)

Galecaster Colossus

Tap an untapped Wizard you control: Return target nonland permanent you don't control to its owner's hand.

Undersea Invader

Flash (You may cast this spell any time you could cast an instant.)
Undersea Invader enters tapped.

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.

Island

Magnifying Glass

{T}: Add {C}.
{4}, {T}: Investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Lumengrid Warden

Mnemonic Wall

Defender
When Mnemonic Wall enters, you may return target instant or sorcery card from your graveyard to your hand.

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.

Volatile Fjord

({T}: Add {U} or {R}.)
Volatile Fjord enters tapped.

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.

Hamletback Goliath

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

Volcanic Hammer

Volcanic Hammer deals 3 damage to any target.

Craven Hulk

Warped Landscape

{T}: Add {C}.
{2}, {T}, Sacrifice Warped Landscape: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Cinderheart Giant

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

Furystoke Giant

When Furystoke Giant enters, other creatures you control gain "{T}: This creature deals 2 damage to any target" until end of turn.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Hell to Pay

Hell to Pay deals X damage to target creature. Create a number of tapped Treasure tokens equal to the amount of excess damage dealt to that creature this way.

Highland Lake

Highland Lake enters tapped.
{T}: Add {U} or {R}.

Turn Aside

Counter target spell that targets a permanent you control.

Snow-Covered Mountain

Shock

That's Mine

Create a Treasure token. (Then exile this card. You may cast the creature later from exile.)

Grabby Giant

Reach
{2}{R}, Sacrifice an artifact or land: Draw a card.

Grabby Giant // That's Mine

Tormentor's Helm

Equipped creature gets +1/+1.
Whenever equipped creature becomes blocked, it deals 1 damage to defending player.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Entry Denied

Return target creature you don't control with mana value 3 or less to its owner's hand. (Then exile this card. You may cast the creature later from exile.)

Beluna's Gatekeeper

Beluna's Gatekeeper // Entry Denied

Lunar Force

When an opponent casts a spell, sacrifice Lunar Force and counter that spell.

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.

Scorching Shot

Scorching Shot deals 5 damage to target creature.

Negate

Exultant Cultist

Giant's Amulet

When Giant's Amulet enters, 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}

The Key to the Vault

Whenever equipped creature deals combat damage to a player, look at that many cards from the top of your library. You may exile a nonland card from among them. Put the rest on the bottom of your library in a random order. You may cast the exiled card without paying its mana cost.
Equip {2}{U}

Borderland Behemoth

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

Crumbling Vestige

Crumbling Vestige enters tapped.
When Crumbling Vestige enters, add one mana of any color.
{T}: Add {C}. ({C} represents colorless mana.)

Retreat to Valakut

Landfall — Whenever a land you control enters, choose one —
• Target creature gets +2/+0 until end of turn.
• Target creature can't block this turn.

Squash

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

Crush the Weak

Crush the Weak deals 2 damage to each creature. If a creature dealt damage this way would die this turn, exile it instead.
Foretell {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.)

Magmatic Chasm

Creatures without flying can't block this turn.

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.)

Vivid Creek

Vivid Creek enters tapped with two charge counters on it.
{T}: Add {U}.
{T}, Remove a charge counter from Vivid Creek: Add one mana of any color.

Eroded Canyon

Eroded Canyon enters tapped.
When Eroded Canyon enters, it deals 1 damage to target opponent.
{T}: Add {U} or {R}.

One With the Wind

Enchant creature
Enchanted creature gets +2/+2 and has flying.

Blood Mist

At the beginning of combat on your turn, target creature you control gains double strike until end of turn.

Iron-Fist Pulverizer

Reach
Whenever you cast your second spell each turn, Iron-Fist Pulverizer deals 2 damage to target opponent. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Lat-Nam Adept

Whenever you draw your second card each turn, put a +1/+1 counter on Lat-Nam Adept.

Peculiar Lighthouse

Peculiar Lighthouse enters tapped unless a player has 13 or less life.
{T}: Add {U} or {R}.

Smashing Success

Destroy target artifact or land. If an artifact is destroyed this way, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Brute Strength

Target creature gets +3/+1 and gains trample until end of turn. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Berg Strider

When Berg Strider enters, tap target artifact or creature an opponent controls. If {S} was spent to cast this spell, that permanent doesn't untap during its controller's next untap step. ({S} is mana from a snow source.)

Storm Reading

Draw four cards, then discard two cards. (Then exile this card. You may cast the creature later from exile.)

Galvanic Giant

Whenever you cast a spell with mana value 5 or greater, tap target creature an opponent controls and put a stun counter on it.

Galvanic Giant // Storm Reading

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.

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 or attacks, tap target permanent. It doesn't untap during its controller's next untap step.

Time Ebb

Put target creature on top of its owner's library.

Hill Giant

Thought Vessel

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

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.

Rewind

Counter target spell. Untap up to four lands.

Bearer of the Heavens

When Bearer of the Heavens dies, destroy all permanents at the beginning of the next end step.

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.)

Giant's Grasp

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

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.

Hammerfist Giant

{T}: Hammerfist Giant deals 4 damage to each creature without flying and each player.

Doomskar Titan

When Doomskar Titan enters, 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.)

Drag Under

Return target creature to its owner's hand.
Draw a card.

Senseless Rage

Enchant creature
Enchanted creature gets +2/+2.
Madness {1}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Bandit's Haul

Whenever you commit a crime, put a loot counter on Bandit's Haul. This ability triggers only once each turn. (Targeting opponents, anything they control, and/or cards in their graveyards is a crime.)
{T}: Add one mana of any color.
{2}, {T}, Remove two loot counters from Bandit's Haul: Draw a card.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Manic Scribe

When Manic Scribe enters, each opponent mills three cards.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, that player mills three cards.

Twice the Rage

Target creature gains double strike until end of turn. (Then exile this card. You may cast the creature later from exile.)

Two-Headed Hunter

Menace (This creature can't be blocked except by two or more creatures.)

Two-Headed Hunter // Twice the Rage

Shimmerdrift Vale

Shimmerdrift Vale enters tapped.
As Shimmerdrift Vale enters, choose a color.
{T}: Add one mana of the chosen color.

Jailbreak Scheme

Spree (Choose one or more additional costs.)
+ {3} — Put a +1/+1 counter on target creature. It can't be blocked this turn.
+ {2} — Target artifact or creature's owner puts it on their choice of the top or bottom of their library.