+-- Ground level ---------------------------------+
| > |
| % |
| v\ |
| \ |
| *--* |
| | |
| | > |
| %--* *--*--* |
| |v \ | |
| | \ | |
| % * *--* * |
| v\ / | \ / |
| \ / | \ / |
| *--* * *--* |
| | / | |
| | / | |
| * *--* * |
| | / | |
| | / | |
| *--*--* * |
| / / |
| / / |
| *--*--* *--* |
| | | / |
| | | / |
| * *--*--* |
| | / |
| | / |
| *--* |
| |
+-------------------------------------------------+
+-- Level -1 -------------------------------------+
| |
| * |
| / \ |
| / \ |
| % * * |
| v\ \ \ |
| \ \ \ |
| * * * |
| | | | |
| | | | |
| * * * |
| / | | |
| / | | ^ |
| * * *--% |
| | / |
| | / |
| * * |
| | \ |
| | \ ^ |
| * *--% |
| \ |
| \^ |
| % |
| |
+-------------------------------------------------+
+-- Level -2 -------------------------------------+
| |
| M--*--* |
| \ |
| \ ^ |
| *--% |
| |
+-------------------------------------------------+