Auto-translated
Come on, what's the point of keeping secrets? He'll figure it out, just a little later. And besides, that's exactly why we created the tactics sub-section. =)
Regarding the field – indeed, the typical use case for the field is to protect one of your stacks (not necessarily archers) from melee damage. Then: either the enemy is taken out by a unit (in which case, it's best to also protect the ammunition cart with the unit), or by magic, or a berserker is placed there:smile10:
Important: the unit that is being protected must move first; otherwise, the enemy will immediately reach it when the field disappears on turn 3 (4).
This allows you to defeat legions of neutral and AI troops with minimal forces. Recommended in combination with: Armageddon's Blade, Antimagic, Teleport.