Omochao (Pronounced: Oh-moh-chow) is a robotic chao in the Sonic the Hedgehog video game series. He is used as the "help" feature during the games. After debuting in Sonic Adventure, Omochao was featured in the games Sonic Adventure 2 for Sega Dreamcast, Sonic Adventure 2: Battle for Nintendo GameCube, and Sonic Advance 3 for Game Boy Advance. Most recently, he has been included in Sonic Generations, though he can be turned off. He appears throughout the levels and is activated when touched. He also appears as the menu navigator and on the Sea Gate level in Sonic Heroes and as Cream the Rabbit's chao bombs in Sonic Battle, as well as the announcer in Sonic Riders and Sonic Free Riders.
In Sonic Adventure, Omochao only appears in the Chao Race stadium in Station Square's Chao Garden, and serves no role other than decoration.
The robot's origin in the storyline is unknown; Omochao simply 'turns up' without explanation in Sonic Adventure 2.
Omochao is often the source of major abuse, as many players find his "help" more annoying than helpful. The little robot can be picked up and thrown as well as used to destroy enemies (He often hints at this, saying in reverse, "I'm not a weapon to throw at enemies, you know!"), as well as be damaged by stray bullets or attacks. After recovering from being thrown (or his injury), Omochao says one of a variety of phrases indicating his displeasure at being used as a weapon or being shot at. Comically, he may also state that he won't help you anymore (which is a lie, of course) or that he can't remember who or where he was.
In Sonic Riders, he was featured as an overly critical announcer, even declaring the slightest mistakes as race-threatening. Again, his comments are extremely annoying, more so now that they directly attack the player and how he/she plays the game. Even landing a "B" ranked trick causes Omochao to say something extremely critical. He also may note a character is "going too fast", which seems out of place in both a Sonic game and a Racing game. Things he'll criticize the player for are overall momentum, race starts, and trick landings, even if these tricks were caused by something like an unexpected push from a rival or turbulance surfing. He also appeared in the Sand Ruin/Dark Dessert cutscenes, where he broadcasted the final race, and dubbed the GP interupted while Jet the Hawk and Dr. Eggman revealed the Babylon Garden. He did not return for Sonic Riders: Zero Gravity, probably because an announcer was not necessary. In the next Sonic Riders game, Sonic Free Riders, he is served as the commentator in various story lines.
Omochao's name is a play on the Japanese word omocha, which means "toy". In Japan, he possess a verbal tic (at least in Sonic Adventure 2) - all of his sentences end in "chao".
There is also a weapon in Shadow the Hedgehog, the Omochao gun, that fired Omochao heads at the foes. It was among the game's most powerful weapons, probably referencing to his previous roles as possible weapons in Sonic Adventure 2 and Sonic Battle.
Omachao appears once again in Sonic Generations as a guide for the player, often giving the player advice and introducing him/her to the controls. He is only optional, though, as he can be turned on and off on the options screen. Omachao also appears on the loading screen to remind players of controls, objects and other features.
Cinossu has made a hack of Sonic 1, called Sonic the Hedgehog OmoChao Edition where you must avoid various objects or Omochao will tell messages to "advise" you what to do. But this is not true. Instead, Omachao states the obvious when Sonic interacts with most things present in the game, making him more of a hindrance than a help.