Opal Sky is a Pegasus Pony that was originally born in Cloudsdale but recently moved to Ponyville. His cutie mark is that of a polished Opal and signifies his talent for making things shine, specifically the weather. He used to be employed in the Weather Factory on Cloudsdale, though if you ask him about it you'll find he doesn't like to talk very much about it. He will tell you however that he was the best engineer that the factory could have asked for.

Since coming to Ponyville he's started working in his cottage (positioned near the edge of the Everfree forest) to produce machinery that can monitor the weather without the involvement of pegasi or the City of Cloudsdale. This hasn't been a very successful endeavor and more often than not you can hear the load booming explosions of his experiments more than anything else.

Opal Sky is an extreme insomniac and more often then not can be found intaking massive amounts of sugar and caffeine as his primary diet. His favorite hangouts being Sugarcube Corner and Tea Rose's Cafe as a result of this.