Sword Question

Are tier 15 Swords better then that one? (currently lvl 50) And could u give me some tipps what i should do with the sword? Power up and all

It needs to be powered up is all.

And what do i have to do with special for this weapon?

The special tab is where you find the transfer upgrade option, the transendendece option (raises tier level), and the reset item stats option. These options are available for all of your equipment.