Giant rock crab

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 target them gives the message "Invalid target."

Giant Rock Crabs are good droppers of charms, as they drop 3 of them at a time. They also drop various black equipment (platebody and claws), worth a decent sum of coins. They are the only droppers of rock-shell parts, which are needed to create Rock-shell armour.

Locations

 * In the Waterbirth Island Dungeon.
 * In the Chaos Tunnels (the middle south rift just east of Mage of Zamorak leads directly to them).

Strategy
Giant Rock Crabs have a fairly high resistance to Melee and Ranged attacks, and thus are only effectively killed using Magic.

In the Chaos Tunnels, they will eventually lose aggression. When they do, just leave the cave via the rope exit. Then just go straight back down the crevice.

Retreat
The Giant Rock Crab is one of few monsters that will retreat from battle when they become critically wounded.

Trivia

 * After the 27 May 2009 update, Giant Rock Crabs dropped Charms in groups of three instead of ten. This hidden update initially angered players, though complaints died down as the rate of charm dropping was also increased.

Giant Rock Crab Giant Rock Crab