Tumfoids were small two-legged robots that were often found near Gelatonium plants. They were built by the managers of these plants to prevent workers from bouncing on the Gelatonium cubes, as the Tumfoid would promptly feast upon said cubes and discourage their silliness. However, on some occasions, these machines soon become a nuisance, since they would begin feast upon all the Gelatonium, requiring Fossermites to scare them away.
The best way to have dealt with these Gel-hungry creatures was to give them their own cube to snack on, then to have quickly shot another one or two cubes for yourself while they were distracted. Another great strategy was to simply shoot them with the Gel to get them stuck inside the cubes for a short time. One strategy that took a while (but was the only way to permanently rid yourself of them) was to knock them into rivers of gel inside the plants with the wrench (or shoot them with gel cubes and free them with the wrench, as this caused them to fly back) and send them to the Gelatonium plant in the sky. Another much more easier way was to throw a Groovitron at them, they will immediately start dancing giving you time to lay down some Gelatonium.
- In Ratchet & Clank Future: Tools of Destruction it was revealed that Slim Cognito was arrested and sent to Zordoom Prison on Viceron for showing his class B gravity cannon to group of female Tumfoids during a rock concert in Meridian City.
- When Ratchet asked the Smuggler why he had traveled to Sargasso, he said that he had trafficked Fossermites for the Kerchu, to have the Tumfoids scared. This must have meant that if somebody had tamed the Fossermites (but were never been seen by Ratchet as they were purely a mentioning), it would be the only way to permanently get rid of the Tumfoids, as they could not die.
- They bore a lot of resemblance to the Tetramites in Ratchet & Clank Future: A Crack in Time.
- In the Spanish version of Ratchet & Clank Future: Tools of Destruction, there is a mistake in the translation in the previously mentioned conversation with the Smuggler, which is that Tumfoid is translated like Omnívoros (omnivores).
- Ratchet & Clank Future: Tools of Destruction (first appearance)
- Ratchet & Clank: Into the Nexus (statue and mentioned only)