opportunity fire

[Crossroads]

That's pretty much the deal you've got.

It is perfectly possible your enemy will test your op fire with sending out his less valuable units first, and after you've exhausted your action points then charge in for a kill.

Your op fire will be targeted against units that move, if you have many targets, but none of them uses any of their action points, your op fire will not fire.

First of them moves, he possibly gets shot at, here's where the die roll comes in.

Mind you, digging in will cause op fire as well. On the other hand, some units such as snipers may be able to sneak in without causing op fire.

There is a good discussion on op fire in the document Jason has put together, it is in the Manual folder of your install. It mainly has to do as figuring out the proper values for each type of Op fire in the dialogue though.

Hope this helps.