Form words that contain evil red tiles to eliminate them. Protect the castle tile from being attacked by the red tiles. Click a letter and drag to form a word. Click the last letter to submit the word.
As the game progresses you'll encounter new tiles, these tiles can be helpful or harmful. You can also earn money by forming words with certain values. Money can be used to purchase a custom letter to add to the board to form that big word you want to make, or to purchase power ups.