The Evil Wave
The Evil Wave is the rarest wave in Toilet Tower Defense, only spawning 2 toilets, Teacher Toilet and Student Toilet, this is exclusive on all modes except endless mode because endless mode can increase the Toilets (from evil wave) health by 1 Billion, and once it happens, you cannot skip the next wave. (Mentioned by Telanthric
Chances on Happening: 0.1% Chance
Can you get it multiple times: yes
When Evil Wave Starts:
Wave Name: evil wave
Annoucement: The evil wave has started
Reward Message: You got the badge and 1,000 coins for beating the evil wave!
Example on Beating the Evil Wave, You will have a seperated from Total Collection and Evil Wave Collection (This works when you win or lose at the game after beating the Evil Wave) (I am not sure if it will count getting 250-500 coins if you do not beat the evil wave)