The Sceptre of Donar is a short ancient staff with a crystal embedded within it that has the power to summon and augment the Harasvelg.
In ancient times, the Harasvelg was often called upon through the Sceptre of Donar to protect northern Scandinavian tribes from their enemies but the Harasvelg became too difficult to control and it turned against the Scandinavians themselves. It caused unbelievable devastation and destruction. They swore to never call upon it again 100 generations later, in 1997, the Sceptre was on display at the New Oslo Scandinavian Folk Museum in New Oslo. Young Swen Christianson wanted to use the Sceptre to summon Harasvelg and save his family's crop from a drought. He stole the Sceptre from the museum and summoned the Harasvelg. However, the incantation that accompanied the Sceptre was destroyed by lightning.
The Sceptre was returned to the museum, locked up, and guarded. The curator refused to let it leave the museum or allow anyone to study it. Slimer secretly flew to New Oslo, stole the Sceptre, and returned to New York City. He mistakenly revitalized the weakened Harasvelg. Kylie Griffin swiped the Sceptre and came up with a plan to use it to defeat the Harasvelg. Eduardo Rivera volunteered to hold up the Sceptre while the others aimed for the crystal. The plan was a success and the Proton Streams were augmented.