The Ring of the Ram in D&D does 1, 2 or 3d6 damage in the form of a ramming attack depending on how many charges are used. My version is a daily item embedded with Vacuum I (3rd level Gas Destruction, Sorcerer Base) three times a day.

The Vacuum effct delivers a single impact critical severity B. I thnk the damage it delivers is slightly less than the D&D version but it does not have a limited number of charges so on balance I think it is on a par.

Ring of the Ram

This is a brilliant imagining of the Ring of the Ram