Bloodfray Giant

Trample
Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Boros Keyrune

{T}: Add {R} or {W}.
{R}{W}: Boros Keyrune becomes a 1/1 red and white Soldier artifact creature with double strike until end of turn. (It deals both first-strike and regular combat damage.)

Callous Giant

If a source would deal 3 or less damage to Callous Giant, prevent that damage.

Skyraker Giant

Reach (This creature can block creatures with flying.)

Stone Giant

{T}: Target creature you control with toughness less than Stone Giant's power gains flying until end of turn. Destroy that creature at the beginning of the next end step.

Craven Giant

Ivory Guardians

Protection from red
Creatures named Ivory Guardians get +1/+1 as long as an opponent controls a nontoken red permanent.

Bulwark Giant

When Bulwark Giant enters, you gain 5 life.

Giant Harbinger

When Giant Harbinger enters, you may search your library for a Giant card, reveal it, then shuffle and put that card on top.

Hammer Dropper

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)

Lowland Giant

Gratuitous Violence

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

Flowstone Giant

{R}: Flowstone Giant gets +2/-2 until end of turn.

Hundred-Handed One

Vigilance
{3}{W}{W}{W}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)
As long as Hundred-Handed One is monstrous, it has reach and can block an additional ninety-nine creatures each combat.

Towering Thunderfist

{W}: Towering Thunderfist gains vigilance until end of turn.

Shatterskull Giant

Ageless Sentinels

Defender (This creature can't attack.)
Flying
When Ageless Sentinels blocks, it becomes a Bird Giant, and it loses defender. (It's no longer a Wall. This effect lasts indefinitely.)

Hamletback Goliath

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

Desolation Giant

Kicker {W}{W} (You may pay an additional {W}{W} as you cast this spell.)
When Desolation Giant enters, destroy all other creatures you control. If it was kicked, destroy all other creatures instead.

Rumbling Sentry

Armillary Sphere

{2}, {T}, Sacrifice Armillary Sphere: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

Fomori Nomad

Pyroclasm

Pyroclasm deals 2 damage to each 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.

Countryside Crusher

At the beginning of your upkeep, reveal the top card of your library. If it's a land card, put it into your graveyard and repeat this process.
Whenever a land card is put into your graveyard from anywhere, put a +1/+1 counter on Countryside Crusher.

Giant's Ire

Giant's Ire deals 4 damage to target player or planeswalker. If you control a Giant, draw a card.

Ancient Amphitheater

As Ancient Amphitheater enters, you may reveal a Giant card from your hand. If you don't, Ancient Amphitheater enters tapped.
{T}: Add {R} or {W}.

Boros Signet

Foriysian Totem

{T}: Add {R}.
{4}{R}: Foriysian Totem becomes a 4/4 red Giant artifact creature with trample until end of turn.
As long as Foriysian Totem is a creature, it can block an additional creature each combat.

Boros Guildgate

This land enters tapped.
{T}: Add {R} or {W}.

Sunhome Enforcer

Whenever Sunhome Enforcer deals combat damage, you gain that much life.
{1}{R}: Sunhome Enforcer gets +1/+0 until end of turn.

Jareth, Leonine Titan

Whenever Jareth, Leonine Titan blocks, it gets +7/+7 until end of turn.
{W}: Jareth gains protection from the color of your choice until end of turn.

Brion Stoutarm

Lifelink
{R}, {T}, Sacrifice another creature: Brion Stoutarm deals damage equal to the sacrificed creature's power to target player or planeswalker.

Awaken the Ancient

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

Palisade Giant

All damage that would be dealt to you and other permanents you control is dealt to Palisade Giant instead.

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.