The help page is obviously not working, probably because a wall-of-text is not the way to go to explain how the game works, so we decided to develop an interactive tutorial!
The tutorial puts the player in a small map against a bunch of enemy units; a balloon shows a simple text that guides the player on each step explaining what to do and ho to do it. The tutorial takes less than 5 minutes to complete and can be played even before creating a new account.
The direct link to the tutorial is the following: