Lvl Ranges from the 70's to 90's
Dagganoths are found in the Waterbirth Dungeon and the LightHouse Dugeon. They can be accessed by completing Horror From The Deep or taking the longboat from Relleka to WaterBirth. These beast are a bit low leveled but have extremely high strength and defense they have maxed out a 17 on me with full rune so bring plenty of prayer pots and food.
The island is really dangerous full of dagganoths at the dungeon but has great rewards. To enter more into the dungeon you'll have to pass the door mechanism for that you will need you and a friend. Step on the two circular plates that are near the door your friend will get the opposite one of course to enter.
There are three lvl 303 Dagganoth King that lurk very deep within the Waterbirth Dungeon. They are very powerful and drop some overpriced items.These beasts are know as The Dagganoth Kings. The name of the strongest is the Dagganoth Rex, Dagganoth Supreme, and Dagganoth Prime. There drops that are known are: Dragon Axe, Seers Ring, farseeer ring,warrior ring,beserker ring,archer ring.More soon to come.