Coalblack

Coalblack was Prince Rilian's horse during his stay in Underland. There is no mention of where Coalblack originally came from or how he came to be in possession of the Lady of the Green Kirtle.

During the Prince's time in the North, he would occassionally ride Coalblack with the Lady of the Green Kirtle on her horse, Snowflake, in Overland around Ettinsmoor and Harfang, always clad in black armour, which is where he got the title "The Black Knight".

When the Lady of the Green Kirtle was killed, Coalblack was ridden by the Prince during the Fall of Underland with Jill Pole to Narnia, while Eustace and Puddleglum rode Snowflake. It is most likely that both Coalblack and Snowflake remained with Rilian in Narnia for the rest of their lives.

Appearance
Coalblack was a pure black stallion.

Coalblack