When you press "Start" (n) you will see a "wave" of
insects entering the arena and moving from top to
bottom and from left to right towards the "exits" of the
arena. Each time a bug reaches the opposite side of
the arena, you will loose one "life point". The amount
of life points is shown in the center of the menu-flower.
Construct barriers to prevent the bugs from finding the
exit. Place the forces of nature (synonym: building
blocks or towers) from the menu-flower where ever you
want inside of the arena. Depending on your wealth
(coins) you have to choose which "elemental" tower fits
best according to the "elemental" bugs. Towers can be
upgraded! It's often better to upgrade towers than to
buy new ones. Every elemental force has its own
damage value and range...