A Silly Particle is a particle of pure silliness that was discovered by Doctor Fissionton, with the assistance of Loony Labs' C.A.K.E. team, during his research on several types of particles. Silly Particles were said to cause absolute wackiness that could be key to driving the Cogs out of Toontown.
On March 29, 2018, Doctor Fissionton used a formula that would allow Silly Particles to appear visible across all of Toontown. Thanks to his formula, a Silly Particle search began, in which Toons had to work together to find Silly Particles all over Toontown. Toons were expected to collect 2,600,000 Silly Particles to help Doctor Surlee with his research while he focused on analyzing a certain fire hydrant. A Toon could collect up to 31 Silly Particles before being unable to collect any more. For every five Silly Particles that was collected, a message from Loony Labs would appear after collecting five. Once a Toon collected 31 Silly Particles, they were instructed to visit Doctor Surlee in Silly Street to trade for five jellybeans per Silly Particle.
After previously been able to collect only 31 Silly Particles, the silliness of April Toons Week increased the limit to 50 and became worth double in value. This sped up the process of the Silly Particle search drastically, eventually allowing Toons to move onto the next phase of the event. After 2,600,000 Silly Particles were successfully collected on April 3, 2018, Professor Prepostera visited Silly Street to offer a ToonTask that would allow Toons to gain access to Doctor Fissionton's location. On April 26th, the ToonTask expired and Silly Particles mysteriously vanished.
- Besides Silly Particles, other types of particles called Antisillions, Glitchinitives, and Phooeytons were discovered, as documented in Doctor Fissionton's "Newly Discovered Particles" text file. The C.A.K.E. team continued their research and discovered more particles called Glue-on, Quirks, and Zaptions, as documented in Doctor Fissionton's "Categorizing Continues" text file.
- Unlike treasures, Silly Particles could spawn in very obscure locations that may force Toons to venture outside of a single zone. Some Silly Particles could also spawn in the Grey.
- Many Silly Particles spawned when the Fissiontons made their final exit during the first maxing of the Silly Meter on March 13, 2019.
- A Silly Particle icon is used to indicate 100 Silly Points for the Silly Meter that are triggered by the Cartoonival Cavalcade as a reward when candles on the parade float are lit.
A Silly Particle by a fire hydrant and the Silly Street tunnel.