Was it a TROLL crawling up above the Czech Republic? (UPDATED)
From Sopron, Hungary, several amazing sprites have been captured and something else, too... See the movie.
I guess it was a TROLL (Transient Red Optical Luminous Lineament). It is visible only on 2 video frames (1 frame covers 20 ms time interval). Here's a still image.
Feel free to leave a comment!
There are differences between this event and those which have been observed in the US (Lyons et al, 2000), which suggest that what we have seen here is something other than a classic troll. (Please see the comments as well.) The most important difference is in the speed: US trolls crawl slowly upward, they are visible for 100 ms or a bit even more. Their head is less compact. On the other hand our event lasted for 40 ms maximum and its head was like an arrow head. Othervise the behaviour of the two TLEs seems to be rather similar. So I think I keep the name but I am going to call this guy a "quickie troll" to distinguish him from his relatives in the US.