Razer Lancehead Tournament Edition mouse not working after updating

Are you using any of the razer packages?

pacman -Qs razer

If you were using one from the AUR you should rebuild it.
But please report if/what packages are in use.

Also … is everything up to date? Fully?

Do you have any skipped pacnews?

pacdiff -o

And of course theres always system info … like running kernel, etc.