Firebird

Not to be confused with phoenixes, firebirds are believed to be an ill omen, when spotted. They are basically giant beasts made entirely of flame, their wingspan going well over five meters.
Some believe they are the souls of the innocent people burnt at the stakes during witch trials, coming to take their revenge and cleanse the world of evil, that led to their death.
Last time it was reported to be seen was during the battle of Heissengrad but there is no factual evidence, only tales. The one that is spread the most between the people goes something like this:
At first they could hear it sing, but of course, they thought it was the roaring engines of tanks and the creaking metal. And then a big wave of smoke enveloped the entire battlefield and suddenly, it was like a second sun has appeared on the horizon. In one, swooping motion the giant bird advanced swiftly towards the - now stopped - enemy army and enveloped them in their wings. It cried again and when the smoke cleared, the entire army was gone. No bodies or machines left, nothing. Just tracks in the ground stopping right in their middle. This is usually explained as there was some kind of a new bomb hidden in the ground or something and the explosion simply might have looked like a bird with giant wings.
But the firebird returned and now it gets weird. This time, there is a person riding on it's back and landing with it just outside the army camp. The bird then transformed itself into a big flaming circle, sort of like a podium on the ground and the cloaked figure spoke to the startled soldiers before it, but nobody really understood what it said, speaking in totally foreign language that nobody has ever heard before. Then it vanished, leaving only a golden feather after itself.
Where the feather is now is also a mystery.

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It was probably an angel of some kind.