Bug? Rule I am unaware of? Am I just stupid?

[Arryn]

The Panther said:
I admit that I have never seen that gateway stone before. I didn't even know it existed, and it is not in the manual.

I call your attention to item 5.52 on page 61 of the manual: Gate Stone.

[The Panther]

Well, don't that beat all. My manual does not have a page 61. The highest artifact on my list is 5.49, the magic lamp.

I wonder what else I am missing...

[Arryn]

You're missing the back side of page 61 as well (pg 62). Artifacts go through 5.65.

You're missing such goodies as:

5.52 Gate Stone
5.53 Alchemist's Stone
5.54 Orb of Atlantis
5.60 The Black Book of Secrets

and drumroll please ...

5.63 The Chalice

[Cheezeninja]

I hate to point out the most obvious thing that comes to mind... but were you viewing a v2.12 battle with v2.13 dominions? If you were, and still have the turn available, i'd suggest loading up 2.12 dominions and having a gander at the battle again.