First major appearance by a demon and then the Angel Hayyel.
De Allyon made his move for world (or at least U.S. vamp) domination, attacking other vamps with the vamp plague.
Jane killed his ass. Cut off his head. Whatever.
Timewalking circle in Natchez.
We found iron ingots from the Spike of Golgotha in Natchez in pocket watches. Bethany and Sabina mention the “vessel” that can hold blood—Holy Grail? Or were they being vampy, inexplicable, and referring to something else?
First appearance of spidey vamps (with exoskeletons) was in Natchez.
First time we found a timewalking circle was in Natchez, and that killed lots of witches.
Le Batard came to town. Grégoire killed his ass. Cut off his head. Whatever.
If Adan knew the arcenciels wanted to destroy vamp timelines, he might be willing to trap and use them to keep that from happening. Or he pretended to be imprisoned in order to obtain trapped arcenciels for his own purposes. Or—who knows what Leo was planning. He was a sneaky bastard.
Ka was possibly a prisoner of the enemy, which forced Adan to do their bidding.