Email Campaign

Basically the players are supposed to find several powerful weapons throughout the campaign, I don’t have access to the Weapons of Legacy supplement and would like some suggestions on how to make an artefact that the players will have to learn more about to use properly, beyond “utter generic magic word and sword bursts into flames” I’m planning for four such weapons each tied to a different element, the whole earth, fire, water, air, deal. Any suggestions, thoughts, ideas, etc would be welcomed and appreciated.