Squash

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

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}.)

Giant's Amulet

When this Equipment enters, you may pay {3}{U}. If you do, create a 4/4 blue Giant Wizard creature token, then attach this Equipment 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}

Fire Giant's Fury

Target Giant you control gets +2/+2 and gains trample until end of turn. Whenever it deals combat damage to a player this turn, exile that many cards from the top of your library. Until the end of your next turn, you may play those cards.

Frost Bite

Frost Bite deals 2 damage to target creature or planeswalker. If you control three or more snow permanents, it deals 3 damage instead.

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, this Saga deals 2 damage to target opponent or planeswalker.
III — The next Giant spell you cast this turn costs {2} 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.

Abrade

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

Volatile Fjord

({T}: Add {U} or {R}.)
This land enters tapped.

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 this card from your graveyard by paying {U} rather than paying its mana cost. If you cast this card this way and it would be put into your graveyard, exile it instead.

Giant's Grasp

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

Basalt Ravager

When this creature 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.