You must save her by making your away across fiendishly difficult 2D levels where everything can kill you.

Maintaining that level of excellence would have been fiendishly difficult.

Reprogramming, without the master's agreement, was as a rule fiendishly difficult.

But a test that makes good sense in theory can prove fiendishly difficult to use in practice.

What is in question, and fiendishly difficult to prove, are the effects of the changes.

Some people find it fiendishly difficult to make that third toss.

But real, useful quantum computers, for all their interest and potential, have proved fiendishly difficult to build.

"Birthday Offering" has some fiendishly difficult changes of direction and balance in its variations for six women.

The partnering, with its changes in speed and direction, is fiendishly difficult.

Such a network with its power and flexibility is easy to describe but fiendishly difficult to implement.