Hello, I would like to know how I can do so that users can use abilities that destroy or change blocks in protected areas with World Guard

/mconfig configure config region_manager_enabled false

Will turn off the WorldGuard integration

thanks ^^ and also, is there a way to make the wands usable in MobArena?

Sorry I missed your second question, but yes see here for info on setting up MobArena classes that have wands in them:

https://github.com/elBukkit/MagicPlugin/wiki/MobArena