Behind the castle is a ladder that leads underground. Proceed and you will find 3 paths. Take the path at the middle and you'll discover a large open space with RuneScape gold a whole lot of level 250 demons. Kill one of them and it will drop its mind. Use the head with some cloth (you need 10) and then cover it with a needle and string. Get a team from Zaff or another player and use it with the mind to turn it into a head on a stick. Being it to Willus along with the creature is going to be finished. Obviously such creature's don't just come to existence. Willus will provide you a letter to bring to Merlin asking he will help to bring the creature to life. Merlin doesn't want to support the creature, therefore bribe him with 50gp. He gives you some Magical Essence and informs you it can be smithed to a heart. Use it with an anvil to Find a Magical Heart. (gives 500 Smithing experience) Bring the heart to Willus to complete the creature. Presently a cutscene will play and the monster will break down a castle wall and dive to the ocean where you can't get to it. Yet. Speak to Willus and he'll inform you about a magical armor known as"Merma Armor" that allows you to breathe underwater. The substance to create it is a rare ore which may only be found submerged. Get your swimming equipment and have Murphy bring you submerged. Near the crabs is a crack in the stone that it is possible to go via (50 Agility demanded ) for an underwater mine which has the ore you need. Mine about 25 of these and then head back to Willus. He provides you with Cheap RS gold a Magical Chisel. There are three pieces: the Merma Top, the Merma Leggings along with the Merma Mask. You want 60 Defence to wear it.