Yellow Wisps are very fond of earth and water. Their powers allow Sonic to transform into the Yellow Drill to reach underground and underwater spots quickly. — Description of the Yellow Wisp, Sonic Colors[1]
The Yellow Wisps resemble White Wisps, except they have triangular heads with one orange eye in the middle. Their heads are covered in orange and yellow stripes, making them resemble drills. They also have three tentacles stemming from their heads.
Infant Yellow Wisps have shorter and smoother tentacles. The corners of their heads are also more round.
Game appearances
Sonic Colors
The Yellow Wisps made their first appearance in both versions of Sonic Colors. When their homeworld was moved to Earth by Dr. Eggman to create his interstellar amusement park, the Yellow Wisps and the rest of their race were threatened to be enslaved by Eggman, who wanted their Hyper-go-on to control the mind of everyone on Earth using a weapon. Fortunately, the Yellow Wisps and the rest of their race were all freed thanks to Sonic the Hedgehog. After Dr. Eggman's Incredible Interstellar Amusement Park imploded into a black hole, the Yellow Wisps worked together with the rest of their race to stop the black hole and succeeded, before returning their homeworlds to their original places in the universe.
Mario & Sonic at the Sochi 2014 Olympic Winter Games
In Mario & Sonic at the Sochi 2014 Olympic Winter Games, the Yellow Wisp makes an appearance during the Dream Event "Sonic's Figure Skating Spectacular". Here, a Yellow Wisp is one of the Wisps that the four participating characters free from a Wisp Capsule as the player(s) proceed down the event's course. When the player then has to defeat the Rotatatron, the Yellow Wisp will appear alongside several others Wisps and join up with the four characters to perform the Final Color Blaster, which deals the final blow on the Rotatatron.
Sonic Runners
In Sonic Runners, the Yellow Wisps play supporting roles to the main cast. Here, it is revealed that some Yellow Wisps chose to stay on earth after the events of Sonic Colors because they liked it there, and that they have established their own small colonies on the planet. Over the course of the game, Team Sonic comes across the Yellow Wisps several times, whom they often end up saving from Dr. Eggman and/or his lackeys. Occasionally, the Yellow Wisps will also ask the team for help solving different problems, whether it be either Eggman-related trouble or more personal issues. Sometimes though, the Yellow Wisps will help Team Sonic as well, usually by providing information or handling smaller tasks.
In gameplay, the Yellow Wisps appear as a part of the Yellow Drill Equippable Item which the player can use during the stages to transform into the Yellow Drill.
In Team Sonic Racing, the Yellow Wisps appear as Item Box power-ups on the game's race tracks. In gameplay, the Yellow Wisp power-ups gives the player the Yellow Drill's power, proving them wih a massive boost through the track that damages all rivals the user makes contact with.
Being Wisps, the Yellow Wisps are halcyon and social. Overall, they are peaceful, playful, non-hostile and friendly of nature, and enjoy spending most of their time playing with others. While they are not fighters, they are nonetheless brave and very helpful towards their friends and allies.
Yellow Wisps are very energetic and playful. They are naturalistic by nature and are very fond of earth and water.[1]
Powers and abilities
The Yellow Wisps are able to levitate in midair at will, which serves as their main method of transportation.
The Yellow Wisps are able to generate and store their own unique variant of a powerful energy known as Hyper-go-on inside their own bodies, which is their life source. It is unclear to what extent they can use their own Hyper-go-on, through they have been shown being able to use it to revert Nega-Wisps back to normal, carry objects through levitation and teleport objects.
The Yellow Wisps are able to pass on a fraction of their Hyper-go by phasing into the recipient. When organic beings or robots receive their Hyper-go-on, they can transform into the Yellow Drill which can drill through underground or move through water like a torpedo.
In the comics, some Yellow Wisps and a few other Wisps were chased by Orbot, Cubot and a pack of Egg Pawns, but one Yellow Wisp was saved by Sonic. After Sonic destroyed the Egg Pawns and send Orbot and Cubot running. A Yellow Wisp then joined Sonic, Tails, Yacker and some other Wisps, as Sonic ventured out to save the Wisp race from Eggman.
In the Sonic the Hedgehog comic series and its spin-offs published by IDW Publishing, the Yellow Wisps are aliens from Planet Wisp. Much like in the games, some of them have settled down on Sonic's world where they help out the planet's inhabitants from time to time.
Trivia
According to Sonic, the Yellow Wisps are similar to Knuckles in terms of energetic nature.
An image of the early version of the Yellow Wisp can be found inside the Sonic Colors files, showing them without stripes, each tentacle being in the front and not two in front and one back, and with a blue eye.
In the DS version of Sonic Colors, a Yellow Wisp asks Sonic to 'play' with him in the water, which made Sonic nervous because of his fear of water.
This is one of the five Wisps to appear in Sonic Colors, Sonic Generations, and Sonic Lost World, the others being the White Wisp, the Cyan Wisp, and Orange Wisp and the Red Wisp.
Yellow Wisps are very fond of earth and water. Their powers allow Sonic to transform into the Yellow Drill to reach underground and underwater spots quickly. 
