Giant Rock Crab | OSRS Index

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12
Giant Rock Crab



Released		1 August 2005 (Update)
Members		Yes
Combat level		137
Size		2x2
Examine		No one likes crabs... especially really big ones!
League region		Fremennik✓ Varlamore✓

Combat info

XP bonus		+10%
Max hit		9
Aggressive		Yes
Poisonous		No
Attack style		Crush
Attack speed		4 ticks (2.4 seconds)
Respawn time		50 ticks (30 seconds)

Slayer info

Slayer level		None
Slayer XP		198 xp
Category		Crabs
Assigned by

Combat stats


180	50	80	200	1	1

Aggressive stats


+0	+0	+0	+0	+0	+0

Melee defence


+225		+200		+175

Magic defence


-10			20% weakness

Ranged defence


+250		+250		+80

Immunities

Poison		0% resistance
Venom		0% resistance
Cannons		Not immune
Thralls		Not immune

Open in DPS calculator
Advanced data

Monster ID		2261
Link		MOID

12
Boulder



Released								1 August 2005 (Update)
Members								Yes
Location								Waterbirth Island Dungeon
League region								Fremennik✓
Options								None
Examine								Heavy rock!

Advanced data

NPC ID								2262,14425
Link								MOID

Giant rock crabs are massive versions of the weaker Rock crab. They lie in wait for prey, disguised as large boulders. When approached, they attack, unless they have become tolerant, in which case they remain as "boulders" - attempting to cast a spell on them gives the message "You can't attack this NPC."

Unlike most other crab species, giant rock crabs have very high melee and ranged defence bonuses, and it is recommended to use magic on them, particularly earth spells to take advantage of their elemental weakness.

Giant rock crabs are primarily known for dropping components to create rock-shell armour, along with the rock-shell boots and rock-shell gloves. However, given their defensive stats, players seeking these components are recommended to kill King Sand Crabs instead, as they are far easier to kill.

Locations

Location	Levels	Spawns	Map	League region
Waterbirth Island Dungeon sublevel 1^{[T 1]}	137	27	Show map	Fremennik✓
Waterbirth Island Dungeon sublevel 2^{[T 1]}	137	5	Show map	Fremennik✓
Waterbirth Island Dungeon sublevel 3^{[T 1]}	137	6	Show map	Fremennik✓
Waterbirth Island Dungeon sublevel 5^{[T 1]}	137	3	Show map	Fremennik✓
Tonali Cavern	137	9	Show map	Varlamore✓
Isle of Serpents ^{[T 2]}	137	9	Show map	N/A

^ ^1.0 ^1.1 ^1.2 ^1.3 In Waterbirth Island Dungeon a partner or a pet rock is required to open the door
^ Inaccessible as the island cannot be moored on

Strategy

The giant rock crab is one of few monsters in RuneScape that will retreat from battle when they become critically wounded. This can be troublesome, as they are found in a single-way combat area. This can be prevented by attacking them while their back is turned to a nearby wall, so that they move away from the player and back up into the wall. If they move too far away, the player will follow them and risk being attacked by another rock crab. There are several protruding sections of the walls in the area that can be used as safespots which are ideal as the crabs' main weakness is magic.

If one wishes to use melee, the crabs can be killed deeper into the cave where there are several spawns in multi-way combat. These crabs will still drop their unique items on the drop table.

Drops

Drop rates are estimated based on 1,715 samples from the Drop Rate Project, unless otherwise cited.

100%

	Item	Quantity	Rarity	Price	High Alch
	Bones	1	Always	30	0

Weapons and armour

Item	Quantity	Rarity	Price	High Alch
Steel platebody	1	5/128	927	1,200
Black claws	1	5/128	7,720	216
Black platebody	1	5/128	2,348	2,304
Mithril axe	1	10/128	152	312
Rock-shell gloves	1	2/128	665	390
Rock-shell boots	1	2/128	615	390
Black warhammer	1	5/128	305	588
Adamant longsword	1	5/128	1,651	1,920

Runes

	Item	Quantity	Rarity	Price	High Alch
	Water rune	1–40	10/128	5–200	2–80
	Earth rune	1–40	10/128	5–200	2–80

Herbs

There is a 8/128 chance of rolling the herb drop table.

Item	Quantity	Rarity	Price	High Alch
Grimy guam leaf	1	1/64	189	7
Grimy marrentill	1	1/85.3	185	8
Grimy tarromin	1	1/113.8	120	9
Grimy harralander	1	1/146.3	284	9
Grimy ranarr weed	1	1/186.2	5,262	18
Grimy irit leaf	1	1/256	1,258	10
Grimy avantoe	1	1/341.3	1,341	10
Grimy kwuarm	1	1/409.6	1,814	12
Grimy cadantine	1	1/512	2,076	13
Grimy lantadyme	1	1/682.7	1,232	13
Grimy dwarf weed	1	1/682.7	1,343	14

Seeds

There is a 1/128 chance of rolling the rare seed drop table.

Item	Quantity	Rarity	Price	High Alch
Toadflax seed	1	1/645.9	979	6
Irit seed	1	1/942.7	72	3
Belladonna seed	1	1/975.7	108	106
Poison ivy seed	1	1/1,354.6	13	99
Avantoe seed	1	1/1,381.4	356	4
Cactus seed	1	1/1,453.3	48	59
Potato cactus seed	1	1/1,993.1	9	84
Kwuarm seed	1	1/2,022	2,003	6
Snapdragon seed	1	1/3,033	43,773	36
Cadantine seed	1	1/4,360	5,135	4
Lantadyme seed	1	1/6,066.1	113	5
Snape grass seed	3	1/6,976	45,303	168
Dwarf weed seed	1	1/9,965.7	690	3
Torstol seed	1	1/15,502.2	15,463	42

Talismans

There is a 10/128 chance of rolling the talisman drop table.

Item	Quantity	Rarity	Price	High Alch
Air talisman	1	1/89.6	201	2
Body talisman	1	1/89.6	1,690	2
Earth talisman	1	1/89.6	558	2
Fire talisman	1	1/89.6	4,550	2
Mind talisman	1	1/89.6	1,255	2
Water talisman	1	1/89.6	275	2
Cosmic talisman	1	1/224	187	2
Chaos talisman	1	1/298.7	236	2
Nature talisman	1	1/298.7	268	2

Other

Item	Quantity	Rarity	Price	High Alch
Coins	1–140	10/128	1–140	1–140
Raw lobster	1	10/128	110	42
Raw bass	1	10/128	9	24
Tinderbox	1	10/128	98	0
Casket	1	2/128	714	30
Rock-shell splinter	1	2/128	21,698	36
Rock-shell chunk	1	2/128	10,672	36
Rock-shell shard	1	2/128	17,876	36

Gem drop table

There is a 1/128 chance of rolling the gem drop table.

Item	Quantity	Rarity	Price	High Alch
Nothing	N/A	1/256.47; Never^{[d 1]}	N/A	N/A
Uncut sapphire	1	1/512; 1/260^{[d 2]}	228	15
Uncut emerald	1	1/1,024; 1/520^{[d 2]}	473	30
Uncut ruby	1	1/2,048; 1/1,040^{[d 2]}	1,087	60
Nature talisman	1	1/5,461.33; 1/2,773.33^{[d 2]}	268	2
Uncut diamond	1	1/8,192; 1/4,160^{[d 2]}	2,439	120
Rune javelin	5	1/16,384; 1/8,320^{[d 2]}	675	1,200
Loop half of key	1	1/16,384; 1/8,320^{[d 2]}	9,756	60
Tooth half of key	1	1/16,384; 1/8,320^{[d 2]}	9,887	60
Rune spear	1	1/262,144; 1/15,600^{[d 2]}^{[d 3]}	11,599	12,480
Shield left half	1	1/524,288; 1/31,200^{[d 2]}^{[d 3]}	65,355	66,000
Dragon spear	1	1/699,050.67; 1/41,600^{[d 2]}^{[d 3]}	38,438	37,440

^ The "nothing" drop is removed while wearing a ring of wealth.
^ ^2.00 ^2.01 ^2.02 ^2.03 ^2.04 ^2.05 ^2.06 ^2.07 ^2.08 ^2.09 ^2.10 The drop rate is increased while wearing a ring of wealth due to the "nothing" drop being removed.
^ ^3.0 ^3.1 ^3.2 Only dropped if Legends' Quest has been finished; if not, a talisman is dropped instead.

Tertiary

	Item	Quantity	Rarity	Price	High Alch
	Clue scroll (medium)	1	1/128^{[d 1]}^{[d 2]}^[1]	Not sold	12

^ The medium clue scroll drop rate increases to 1/121 after unlocking the medium Combat Achievements rewards tier.
^ Clue scrolls will drop as scroll boxes after the completion of X Marks the Spot.

Changes

Date	Changes
25 June 2025 (Update)	Giant rock crabs now have a 20% elemental weakness to earth spells and heavy ranged defence reduced from 250 to 80.
26 March 2025 (Update \| poll)	Crabs can now be assigned as a Slayer task by Mazchna, Vannaka, and Chaeldar.

References

^ Jagex. Mod Tide's Twitter account. 24 May 2019. Archived from the original on 24 May 2019. Mod Tide: "I know its been a while since the clue expansion but here is the information on clue scroll drop rates and loot chances! If anything changes I will keep you posted."

Waterbirth Island

NPCs

Dagannoth Kings

	Prime Rex Supreme
Uniques	Archers ring Berserker ring Seers ring Warrior ring Mud battlestaff Seercull

Monsters

Items

Rock-shell armour	Helm Plate Legs Gloves Boots Rock-shell chunk Rock-shell shard Rock-shell splinter
Skeletal armour	Helm Top Bottoms Gloves Boots Fibula piece Ribcage piece Skull piece
Spined armour	Helm Body Chaps Gloves Boots Circular hide Flattened hide Stretched hide
Fremennik helmets	Archer helm Farseer helm Fremennik helm Warrior helm
Other	Dagannoth hide Fremennik blade Fremennik shield Snape grass

Source site	Old School RuneScape Wiki
Canonical source	Giant Rock Crab
Content license	CC BY-NC-SA 3.0
License status	declared
Picture	Giant Rock Crab · file details