God of War Ragnarok contains 5 Shields, none of them are missable.
1 - Dauntless Shield - Purchasable from blacksmith shop
2 - Stone Wall Shield - Purchasable from blacksmith shop
3 - Guardian Shield - Automatic Story Unlock - given by Sindri at start of quest The Word of Fate.
4 - Shatter Star Shield - Found in a Legendary Chest in Vanaheim (The Abandoned Village: after picking up the Lore: Prayer to Freya use the Chaos Blades to pull the rubble out of the way and squeeze through the gap behind it. Follow that linear path until you climb up a golden chain. Then on the right is the Legendary Chest, surrounded by purple mist from a poisonous plant. You must throw the axe at the plant to freeze it, then you can get to the chest.).
5 - Onslaught Shield - Found in Helheim, a Legendary Chest after the Garm boss fight. If you forgot to pick it up here, it will automatically be added to the blacksmith shop and can be bought for 7500 Hacksilver (the location is not accessible anymore after the fight).
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