THE POPULOUS BIBLE
E.5 Casting out of range
Casting out of range is something that should be avoided most of the times. For instance, why casting a light in a far away gather of enemy troops when, if once you reach them, they could be gone? If that happened, you would just waste a lighning in the ground. Really avoid casting spells out of range, specially when playing online, as the enemy is smart and will move the troops before your spell hits them.
Also, some spells like tornado, when being cast out of range in a enemy building, they might be less effective, not destroying the building completly - or sometimes missing it. So, make sure not to cast spells like tornado before you are actually in the range of that building you want to destroy.
Lesson learned - only cast spells inside the range.
It would not be recomendable to click the tornado in this moment, and it is still out of range (see the indicator and the forbidden icon). It the player would click the spell now, the shaman would walk towards that hut, and cast tornado, but it would possible not destroy that hut completly.