+-- Ground level -----------------------------+
| |
| * |
| \ |
| \ |
| * *--* |
| \ | | |
| \ | | |
| * * * |
| / | |
| / | |
| * *--*--* |
| \ / / |
| \ / / |
| * * * |
| \ / |
| \^/ |
| % |
| / \ |
| / \ |
| * * |
| / | |
| / | |
| *--*--* * |
| | \ |
| | \ |
| * * * * |
| | / \ | |
| |/ \ | |
| * *--*--* |
| | |
| | |
| % |
| v |
| |
+---------------------------------------------+
+-- Level -1 ---------------------------------+
| |
| * |
| / \ |
| / \ |
| * * |
| > / |
| ^/ |
| % % |
| > /v |
| < / |
| * |
| |
+---------------------------------------------+
+-- Level -2 ---------------------------------+
| ^ |
| % |
| | |
| | |
| % |
| v |
| |
+---------------------------------------------+
+-- Level -3 ---------------------------------+
| |
| % |
| <v |
| |
| |
| |
| ^ |
| % |
| \ |
| > \ |
| * * |
| \ / |
| \ / |
| * |
| |
+---------------------------------------------+
+-- Level -4 ---------------------------------+
| ^ |
| % |
| v |
| |
+---------------------------------------------+
+-- Level -5 ---------------------------------+
| ^ |
| % |
| v |
| |
+---------------------------------------------+
+-- Level -6 ---------------------------------+
| ^ |
| % |
| | |
| | |
| * |
| | |
| | |
| * |
| | |
| | |
| M |
| |
+---------------------------------------------+