Magic in Heroes of Might and Magic V.

Traps are very useful when fighting neutral creatures, especially for the Elves: invisible hunters, and we fill the area with traps. When the invisibility wears off, the enemy rushes forward, and it's clear what happens to it. Or in the final stages, when you have little mana and few troops left, you can set up traps... Some even manage to capture Utopia using them. In general, there are many uses, depending on the situation.