Quote Originally Posted by Oaty
I've had problems with artillery, and its not there range thats the problem, its the fact that there lowest trajectory is ~zero degrees.

I've noticed artillery fires on from the top of a hill at a greater range but as the enemy comes closer, your cannons can no longer effectively hit the enemy. If there is a green icon but they refuse to fire this is the problem.

The other problem is even if they can aim below zero degrees they will hit the top of the hill.

Not to sure how the game is designed but it does seem the cannons can go below zero degrees at points.

If I set the cannons on the slope of the hill instead of on top there seems to be a lot less problems.
I've noticed this too, and it might be part of the problem that the OP is getting at. Some artillery have maximum and minimum angles of fire. For instance, if you are on top of a mountain that is really steep and the enemy is below and has catapults, they will NEVER be able to fire at you because the angle is too steep and a catapult can't really release it's ammo at a different point to get the correct trajectory. Same goes for some artillery at the top of hills, too, where the trajectory would no longer be able to effectively target troops that are too steeply downhill.