Couldn't find the Grail.
It has the same gimmick as Jedi Story; the Grail is located in a burrow.
It seems like a good map, and the battlefields are interesting. What will you play next?
As far as I understand, it's related to changing the properties of the tin scattered throughout the map.
Yes, it's amusing. I've seen this map, but I didn't check the tin specifically. Have you already played all of Aeris's maps?:)