Elemental Weapons Are Glitched?

No, the client shows the damage on your screen. Sunrise is correct. The damage applied to the mob is generated by the server and the client together.

The client data in the WZ files is intact, but that means nothing if Maplestory.exe is not programmed to read or interpret the value in the WZ file. If what you're suggesting is the current situation, people wearing the elemental staves and wands would be seeing much higher damage client-side than what is being applied on the server.

In short:

Client calculates
Server calculates and applies

Then would that mean that the elemental staves/wands actually have the effect, but it doesn't show up in your client?

So if it shows you doing 10K damage, you're actually doing 15?
(Or is the effect just disabled?)