I did the same. I dug up the GRAIL and placed it. Let anyone try to dispute my right to it. On this "map," playing as Barbarians against a castle is like banging your head against a wall. And my plan was to win using the Grail. First, I opened all the obelisks, including those on the opponent's side (sacrificing my main hero with 2 Behemoths, 2 Phoenixes, and some other minor units). If it weren't for the Grail, there would be no options. No artifacts, no utopias. Just a pure dueling map. And as some people write, that this isn't a measure of skill – then what is a measure of skill? A battle against hundreds of archers and a horde of monks, with expert blessing and a hundred orcs firing. Or: how to kill an Archangel? This was a tactical plan that brought me victory. We played for six and a half hours. And I don't have the opportunity to replay this game with Tieru!!! I've already sacrificed a day off. Please excuse me! I was against replacing Tieru immediately. Waiting for answers!!!

Added 7 minutes later

What isn't forbidden is allowed, especially if there are obelisks on the map.

This is the main thing you should have stuck to! Building the Grail, specifically by opening all the obelisks (in this case, of course, if they are placed fairly – and on this map, they are), is not that easy.