> Now that I've read your post I realize my issue was mostly semantic. I'm totally fine with all three totems being within the cannon, activated by sound, while the filters alter the sound frequency to produce different results. You don't have to switch out filters in battle. I think the daily tuning and risk of "jamming" in battle makes it finicky enough to be fair. Sound good?

Yeah, that sounds great! To reflect this theory better (and to give the totems some physical description, which I hope works for you), I have edited the theory section of the cannon to the following:

The core of the cannon contains three different elemental totems--fire, light, and electricity. These are suspended within the cannon with the use of a metal "claw" and resemble white crystals. When exposed to certain frequencies of sound, these totems can be activated at will and their effects manipulated as their energy passes through a series of adjustable filters/shutters within the cannon's muzzle.