Here is another German folklore with some rather Lovecraftian elements. It's a brief one, so I will quote it in its entirety, but it's so very juicy.

"The legend is widespread in the Holstein region that a rooster who has lived for seven years in the exact same house will then lay an egg. A strange animal will come out of this egg which people call by different names: Dragon, crocodile, and so forth.

A man named Swatkopf lived in the parish of Wewelsfleth. This man had a rooster which, since it had already lived within his house for seven years, laid an egg into the crib for his horses. But a strange thing crawled out of this egg. During the day, it always stayed in the crib for the horses. However, as soon as it became dark, it flew up to the owls’ gable in the house and made fluting noises. Now Swatkopf would have liked to sell his house, but he could not get rid of it. Then he had it torn down and built a different building on the same spot. The animal now moved away from him and to his neighbor Kasten Tumann, and in the evening sat in his chimney as a clump of fire. If Tumann was home, then the fluting thing always looked inside through the window, and caused him no little terror. In the end, Tumann took this so hard that he went to the sea and never returned home. But then the animal was also gone, and no one has seen it again."

While it is lacking in proper Lovecraftian words and phrases such as "squamous", it makes up for being very bizarre. The "Fluting Thing" has no clear appearance, but it drives the locals to madness and exile, and nobody knows what it wants. The notion that a bizarre creature can hatch from a rooster's egg is part of basilisk narratives, but the actual description of the creature is rather different.

(Note: I took the picture myself when I passed through Wewelsfleth last year.)