My interpretation of the mythical Bonnacon, and Shenley's "Vehicle" for the I-D-D tourney over on devART. Flying "vehicles" are forbidden, hence why Shenley isn't using the summon 'Karura'.

Bonnacon is a low-class mystical creature which can be summoned by Shenley. It is about as big as a horse, and although it might not look it, at least as fast as one too. It is also really stupid in comparison to horses, other summonable creatures, and well, anything really.
Its speed and size, as well as the fairly low amount of energy required to summon it, make it an ideal steed for the IDD, which is unfortunate for Shenley who is not particularly fond of the creature. Bonnacon shows a lot of affection for the summoner however.

Its horns curl backwards and in towards each other, thus making them useless as weapons. They do however make for a decent pair of handlebars. Bonnacon is not entirely defenceless though - from its rear it can deploy a powerful foul smelling spray (like a skunk, only much, much worse) and burning dung which can be launched across great distances.
Bonnacon has a thick hide, making it resistant to most regular physical attacks. It is also not affected by extreme heat or cold. That aside, it’s probably too stupid to realise it’s in pain anyway, and will just keep running.

The only noise it makes is best described as a distinctive “MURH!” cry.