First off, Teleport to The Rock Crabs by using the "Monsters Teleport" in you're spellbook and then by clicking the Rock Crabs tab.
When you are teleported, there are 2 types on monsters there -
Rock Crabs ( Level 13 ) -
Drop -
- Green, Crimson, Blue, Gold Charms
- Cut / Uncut Gems
- Bones ( 2 )
- Clue Scroll
Rock crabs are reccomended to train on when you are new as they dont hit anything
and are easy to kill.
On the island, there are also
Goblins ( Level 2 )
Drops -
- Green, Crimson, Gold, Blue Charms
- Bones ( 2 )
Goblins dont really drop anything as they are not reccomended to train on
because they only drop Charms.