From publisher blurb: Himmilgard is a land of a great many dangers, few which are well understood. Some are simple for humans to comprehend: a Grand Eagle will swoop in and tear apart your plane because it is hungry. Others are strange, but their boundaries are known: if you wish to avoid the Fae, don’t stray into the Wild. But in the darkest forests, the deepest caves, and the open ocean are a myriad of dangerous creatures which exist at the level of rumours, half-remembered stories, and blurry photographs. High up in the clouds, too, there are dangers. As the combustion engine has grown more powerful, the airplane and airship swifter and more reliable, people have edged ever closer to this strange realm, ignorant of that which lurks above. For the open air is not as empty as it seems, and that which lurks at these great heights is inimical and alien to human life. While the shape of this threat is known to few, veteran pilots know better than to stray too far from the safety and certainty of solid earth. Flying Circus: Horror of the Heights is a 44 page expansion for Flying Circus, expanding the game's support for high altitude gameplay both in the air and on the ground. This book contains... Expanded rules for high altitudes and extreme conditions, including the effects of changing temperatures with altitude. Rules for turning high altitude gameplay into a maze of terrifying monsters! Special rules for alpine travel on foot and making camp in the harsh wilderness. New character moves and traits for fighting high in the air. New equipment like oxygen tanks and escape balloons, new weapons including sniper rifles and ice axes, and new aircraft modifications like oxidized fuel and lightning-dispersion systems! A variety of new high-altitude threats, like the hypnotic Mimic Moth, the mysterious Flying Fortresses, and the malevolent Lightning Sprites. Also includes revamps, examples, and expansions to Leviathans, Sky Screamers, and Cloud Jellies. Six new aircraft optimized for high altitude work, from the Markgraf Totengräber zeppelin-hunter to the Sonnenjäger Hummel spy plane.