Herby can you provide more info?

I can conclude from testing it lowers magic damage from PVE bosses.

Does it:

1) Lower skill or phys damage against PVE bosses.
2) Lower magic damage in PVP.
3) Lower skill or phys damage in PVP (when the attack is not blocked).

I may be imagining things, but it seems to lower Thousand Strikes damage in PVP, but not Rallying Strike or Driving Blow.