An ultra invasion is a very special event in which cogs flood the streets (and in some cases playgrounds) and must be stopped with out-of-battle gags given to toons. Ultra invasions never happen randomly, as they are event-only occurances. Following this rule, ultra invasions can never be summoned by toons, like a mega invasion. Also like a mega invasion, there are a few "safe districts" (Welcome Valley is always one of them) that are not affected by an event. When an ultra invasions starts, the sky becomes grey, cogs begin flying overhead, sirens begin to sound, and a Toon HQ message saying "Lock the doors! Close the blinds! A state of emergency has been called: an ULTRA INVASION has begun!!!" will appear.
Ultra invasions can only ever be summoned by game staff or by the game itself.
- The first ever ultra invasion was after the release of the Island of Lost Gags, where Vacabots stormed the mainland.
- The ultra invasion also affected the Island of Lost Gags, however it was not mentioned.
- Unlike other types of invasions, ultra invasions do not give any extra gag experience.
- The Doomsday invasion could possibly have counted as an ultra invasion.