But, that isn't always possible. Of course sneaking up on an alert guard can be difficult. To help you Commandos has a feature which allows you to click on any soldier and a green path will show where they are looking. This lets you see how far you can advance without being seen. Without the feature the game would be nearly impossible to complete.
Missions have various tasks to accomplish.
You may need to blow up an entire German base or just blow up certain parts of it. In most cases you'll need to achieve several objectives to complete each mission. The levels are extremely difficult but after precise planning any mission can be conquered. You can also alter the difficulty level to make your job easier. In any case, this is not just your average real time strategy game.