impossible gameplay tactics on XL.

I didn't quite understand the question. Is someone or something standing on the Grail, making it impossible to take? Ideally, it should be under the cross, which you need to stand on. If you want to find it in an invisible area, theoretically it should be in the center of the puzzle, but practically it might be slightly off-center, in which direction is likely random. To avoid searching for a month, try to reveal as much of the puzzle as possible to see at least the edge of the cross.

I reveal as much as I can and try to align it with the map so that the image matches.

When a tree or a rock is in the center of the zone, I dig around it (as close as possible).

So, the cross might not be in the center of the image?

Then it's clear...

Added 1 minute ago

+1, it's quite chubby.

You are wrong, Sir!

P.S. And what does "if you play completely without rules..." mean? Does it mean that the "diplomacy" skill is usually forbidden when people play?

We are really playing without any restrictions (except for those described in the first post - at the beginning of the game).

We sometimes introduce 1-2 computer opponents into the game to add some randomness - otherwise, I am always killed first :-)

And what additional restrictions should be imposed on XL games to make them fairer (at least to newcomers like me)?