Boiled Crab is a consumable item in Elden Ring that enhances your physical damage negation by a huge amount for a particular time period. While there are other permanent solutions to increase your defenses in the game, Boiled Crab acts as an amazing supplement to your tank build.
However, finding Boiled Crabs in Elden Ring is not a simple task. This item is related to the progression of the Blackguard Big Boggart quest, which starts in Liurnia and concludes on Altus Plateau. Let us help you guide through the process and help you acquire an infinite amount of Boiled Crabs in the game.
Find Blackguard Big Boggart in Liurnia
Boiled Crab can only be purchased for 600 Runes each from Blackguard Big Boggart once he moves to Leyndell and sets up his shop there.

There is one caveat regarding the method mentioned above. For Blackguard Big Boggart to move to Altus Plateau, you must progress his quest.

Boggart’s quest is directly linked to Rya’s quest. You can find Rya in the central region of the Liurnia of the Lakes. She will be standing inside a dome just north of the Lakysar Ruins site of grace.
This place is marked with a telescope on the map of Liurnia of the Lakes. Talk to Rya, and she will tell you of a thief who stole her necklace. Rya will ask for your help in retrieving her necklace.

To find the thief, travel northwest of Rya’s current location until you come upon a rundown shack. This place is called Boilprawn Shack and is inhabited by the Blackguard Big Boggart.
You can either attack him or talk to him to get the necklace back. Attacking Boggart will lock you out of his quest, and you won’t be able to get Boiled Crab in Elden Ring until the next playthrough.

Talk to Boggart and offer him 1,000 Runes. He will give you Rya’s necklace. Take the necklace back to Rya and give it to her. Exhaust her dialogue and then return to Boggart. Purchase some Boiled Prawns from him.
This will trigger new dialogues, and he will tell you of his plan to move to Leyndell, the Royal capital.
Purchase Boiled Crab from Boggart on Altus Plateau
Once Boggart becomes your friend, he will move near the entrance of Leyndell, the Royal capital. To find him, start from the Outerwall Battleground site of grace. Go east from there to reach the moat.

Instead of going towards the entrance. Go down the hill and you will notice Boggart sitting near the moat. Talk to him and he will sell you an unlimited supply of Boiled Crabs, each for 600 Runes.
You can also purchase Boiled Crabs and Boiled Prawns from the Twin Maiden Husk in the Roundtable Hold if you kill Blackguard Big Boggart near Leyndell and offer his Bell Bearings. Killing him in Liurnia will only allow you to purchase Boiled Prawns, potentially locking you out from purchasing Boiled Crabs until the next playthrough in Elden Ring.
Boiled Crab Use and Comparison with Boiled Prawns
Boiled Crab in Elden Ring gives you an additional 20% physical damage negation for the next 60 seconds (15% in PvP), in addition to what you already have. This value is dependent on your current physical defense value contributed by your gear and talismans.
This comes in extremely handy against powerful bosses like Godfrey, the first Elden Lord, and the Elden Beast, who hit players like a truck. During these fights, every sliver of your HP matters, and Boiled Crabs provide immense protection against their attacks.
In comparison, Boiled Prawns give you 15% physical damage negation. While they also seem like a good choice, each damage negation percentage plays a critical role in tough battles against bosses. For this reason, we recommend that you stick with Boiled Crabs in Elden Ring.