This activity shows one of the hazards facing the already difficult mission.

I have you in mind for a very delicate and difficult mission.

This just might prove to be a more difficult mission than had been suggested.

It was obvious they had been presented with a difficult mission.

Besides, I was about to set out on a difficult and dangerous mission.

That was the most difficult mission of my career.

It is one of the more difficult and higher paying missions in the game.

The difficult mission is the reason for the rigid training.

Almost every step of the way our troops have been left on these extraordinarily difficult missions.

But what a difficult mission he has before him.