Are the gods invulnerable or not?

[Cardinal Ximenez]

Thinking back to the Perèz run, I get a little confused about something: in the "Gods and Mortals" storyline, Diana kills one of Ares´s sons, a god. Then during Ruckas run, when Ares shows up on Themyscira and an amazon attacks him, he laughs it off, saying no mortal weapon can hurt him. So how did Diana manage to kill his son, another god, with her regular weapons?

[ryerye17]

Wonder Woman's not mortal. Her weapons are not mortal.

[turnedm]

Most of Diana's weapons are god created or blessed. I do however, wonder what is the origin of the tiara. Plus, when Ares was attacked by Io, during Rucka's run, she tells him that the blade she was using was crafted or blessed by Ares himself, so he wasn't laughing when she stabbed him with it.