Promethium maul

A Promethium maul is a weapon used in the Dungeoneering skill. It is made from Promethium ore, requiring 4 bars and a Smithing level of 98 to smith, and a Strength level of 90 to wield. Promethium maul can also be obtained as a drop. It is most commonly dropped by Rammernaut but may also be obtained by high tier Forgotten warriors and Brutes. They will be seen wielding the maul before they are killed.

Dropping monsters
Promethium maul