Bring these to Willus and now he would like you to OSRS gold make a tail. Get about ten cowhides, tan themand then put them together with a needle and string. Today Willus wants you to construct the head. Go down it and you will find 3 paths. Take the path at the middle and you'll discover a big open space with a bunch of level 250 demons. Kill them and it will drop its mind. Use the head with a few cloth (you want 10) and cover it with a needle and cord. Get a team from Zaff or a different participant and use it together with the head to turn it into a head on a pole.
Being it to Willus along with the monster is going to be completed. Of course such monster's do not only come to existence. Willus will give you a letter to deliver to Merlin asking that he helps to bring the creature to life. Merlin does not wish to support the creature, therefore bribe him with 50gp. He gives you some Magical Essence and tells you it can be smithed into a heart. Use it using an anvil to get a Magical Heart. (gives 500 Smithing experience)
Bring the guts to Willus to fill out the monster. Presently a cutscene will play and the creature will break down a castle wall and dive into buy RuneScape gold the ocean where you can't access to it. Yet. Talk to Willus and he will inform you about a magical armor known as"Merma Armor" which allows one to breathe underwater.