g24

This building was constructed with a Gernegross set. The Gernegross set is one of the smallest (is it the smallest?) Anchor Stone block sets. Not only in size, but also in the number of blocks contained in the set. There are only 38 blocks in a Gernegross set.

It's been mentioned that a Gernegross model can be constructed with a Heinzelmannchen set with a few substitutions in block color. It's also possible to construct any Gernegross model with a #6 starter set. One only needs to substitute two #4R blocks for two #4G blocks.

Hints:

g23

Here's another tower design for the Gernegross set. There's no door into the structure. Maybe it's a prison. Be careful when constructing the roof. It's easier to construct the roof on a flat surface, then lift it all at once to place it on the tower.

Here's a GIF animation of the build in progress.