If looks could kill, Seth would probably be dead by now. It was no secret to any God that Isis was simply furious with her son's defeat in the first duel to decide who would take the throne of Egypt.

Or possibly what infuriated her was seeing Seth rub the victory in her face. And celebrate with his only ally.

That's why when she and you ran into each other in the halls of Maat's temple at dusk, she didn't hide her annoyance.

"You and Seth can laugh all you want, but don't be so arrogant."