As a word of warning, occasionally a demon may slip past your defences.  This happens randomly and is the nature of the game unfortunately.  If your Anti-Ninjas end up in a chase, you may need to give them a tap with your stylus so they can catch the demon.

Wave 01
Build a Wee Ninja hut on square 1, and Anti-Ninja huts on squares 2 and 3.  Fast-forward to start the demons.  At the end of the wave, upgrade your Anti-Ninja on square 2.

Wave 02
At the end of the wave upgrade your Anti-Ninja hut on square 3.

Wave 03
You shouldn't need to do anything, just be ready to give your Ninjas a tap if they need to catch a runaway.

Wave 04
Same as the previous wave.

Wave 05
At the end of the wave, upgrade both your Anti-Ninja huts.

Wave 06
You will need to use your wind special power half way through the wave to blow the big demons back towards your ninjas.  At the end of the wave upgrade your Anti-Ninja hut on square 2.

Wave 07
At the end of the wave upgrade your Anti-Ninja hut on square 3.

Wave 08
At the end of the wave upgrade your Anti-Ninja hut on square 2.  This hut should now have 5-stars.

Wave 09
Be ready to use your wind special power when necessary.

Wave 10
Be ready with your wind again, and upgrade your Anti-Ninja hut on square 3 at the end of the wave.

Wave 11
Watch your Anti-Ninjas bring home the victory.