Red Sprites

The hard-to-record Red Sprites are large-scale electric discharges that occur high above thunderstorm clouds, or cumulonimbus, giving rise to a quite varied range of visual shapes flickering in the night sky. They are usually triggered by the discharges of positive lightning between an underlying thundercloud and the ground.
Here a closeup telephoto view of the sprite appears above the city of Split in Croatia from Zvjezdano selo Mosor Observatory on 2021 Oct 4. The second image shows the sprites above a sea of clouds from Alsace, France on 2021 Nov 24.