From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Usagi Ninjinka (と にんじんか, To Ninjinka; FUNimation "Monster Carrot", Viz "Carrot Master"; Literally meaning "Rabbit Carrot Transformer") is an anthropomorphic Rabbit and the leader of the Rabbit Gang. Each of his cronies wear a pair of false rabbit ears. Before they fall at the hands of Son Goku, the Rabbit Gang is in control of a remote town somewhere in the Diablo Desert.
When two Rabbit Gang Members were beaten up by Goku, they contacted Usagi so that he could make a personal appearance at the scene. Despite having plenty of time to make an escape before Usagi arrived, the Dragon Ball Gang opted to stay because they "...want to stay and see what every one around here is so scared of." and would not be scared by "...grown men wearing rabbit ears." Usagi arrived and greeted the group, particularly Bulma, with a handshake. Bulma refused and slapped his hand away. He laughed as he proclaimed, "You touched me." Suddenly with a burst of smoke, Bulma transformed into a Carrot.
Goku attempts to attack Usagi using his Power Pole, but has trouble doing so in fear of something happening to the Carrot Bulma. Yamucha, and Puar, who had been observing the group's conflict from a distance, step into the scene, managing to retrieve the carrot Bulma from Usagi. After losing his trump card, the crime leader is easily defeated and is forced to transform Bulma back into a Human. He and his subordinates are then bound and taken to the Moon by Goku where they continued to live making treats for children (an allusion to "The Rabbit in the Moon", a Japanese folk tale where Rabbits live on the Moon making cookies).
Unfortunately for Usagi and his two followers, the Moon was later destroyed by Turtle Hermit as a permanent solution to stopping Goku from transforming into a Great Ape (since his tail kept growing back), presumably killing them.
Usagi appears as a boss in a level of Dragon Power.
Usagi appears as a boss in a level of Dragon Ball: Origins.
Usagi escaped the Moon and returned to Planet Earth somehow in Dragon Ball Z: Attack of the Saiyans. Sometime after Piccolo Daimao's defeat, he took over Yamucha's Hideout on Mount Paozu. Yamucha was told about this by Puar and returned to stop Usagi. Usagi had become more powerful than before, but was no match for Yamucha. He defeated Usagi and forced him to do chores, such as cleaning the house.
- Usagi and his two minions can somehow breathe in space (possibly because of anime physics).
- Usagi has superhuman jumping abilities. He first uses this ability to dodge Goku's Power Pole and later uses it to try and touch Puar after he grabs Carrot Bulma and takes flight, just barely missing her.
- Magic Touch – The ability to transform any living thing into a Carrot by simply touching it with his hands.
- A capsule you can receive in Attack of the Saiyans has the ability to turn all enemies into Carrots after they are defeated. The Carrots can then be exchanged with a man in Metro West for other items.
- Despite being able to turn anyone into a Carrot by touch, it seems to be an ability he can switch on and off as he is seen touching his men and Goku at separate times.
- There is speculation on where Usagi and his men got the materials to build the spaceship and a power source.
- Usagi has the ability to turn people into Carrots. This is similar to a later villain, Majin Boo, who has the ability to turn people into any food (or clay).