General gameplay tactics and its features.

The field disappears every other turn, actually... :) But under certain circumstances, it's not necessary to have the first turn - you can simply blind the opponent, obliterate them with a devastating beam down to zero, and then hit them hard...

Hmm. I wouldn't want to argue with an expert, but as far as I remember, with the Earth expert, the field lasts for 3 turns - the one it was placed on and 2 more full turns. With the basic earth skill, it lasts for 2 turns. With the advanced one, I don't remember. That's why I wrote in the post that it disappears on the 4th (3rd) turn. I don't have the opportunity to test this right now, so try it yourself. Perhaps this applies to older versions; I don't remember anymore. :)