Massive Caverns
===============

+-- Ground level -----------------------------+
|                                             |
|      *                                      |
|       \                                     |
|        \                                    |
|         *                 *--*              |
|          \                |  |              |
|           \               |  |              |
|            *              *  *              |
|           /               |                 |
|          /                |                 |
|         *           *--*--*                 |
|          \         /     /                  |
|           \       /     /                   |
|            *     *     *                    |
|             \   /                           |
|              \^/                            |
|               %                             |
|              / \                            |
|             /   \                           |
|            *     *                          |
|           /      |                          |
|          /       |                          |
|   *--*--*        *                          |
|   |               \                         |
|   |                \                        |
|   *  *              *        *              |
|   | /                \       |              |
|   |/                  \      |              |
|   *                    *--*--*              |
|                              |              |
|                              |              |
|                              %              |
|                              v              |
|                                             |
+---------------------------------------------+

+-- Level -1 ---------------------------------+
|                                             |
|                              *              |
|                             / \             |
|                            /   \            |
|                           *     *           |
|                            >   /            |
|                              ^/             |
|                              %        %     |
|                               >      /v     |
|                                   < /       |
|                                    *        |
|                                             |
+---------------------------------------------+

+-- Level -2 ---------------------------------+
|                                       ^     |
|                                       %     |
|                                       |     |
|                                       |     |
|                                       %     |
|                                       v     |
|                                             |
+---------------------------------------------+

+-- Level -3 ---------------------------------+
|                                             |
|                                       %     |
|                                      <v     |
|                                             |
|                                             |
|                                             |
|                                       ^     |
|                                       %     |
|                                        \    |
|                                     >   \   |
|                                    *     *  |
|                                     \   /   |
|                                      \ /    |
|                                       *     |
|                                             |
+---------------------------------------------+

+-- Level -4 ---------------------------------+
|                                       ^     |
|                                       %     |
|                                       v     |
|                                             |
+---------------------------------------------+

+-- Level -5 ---------------------------------+
|                                       ^     |
|                                       %     |
|                                       v     |
|                                             |
+---------------------------------------------+

+-- Level -6 ---------------------------------+
|                                       ^     |
|                                       %     |
|                                       |     |
|                                       |     |
|                                       *     |
|                                       |     |
|                                       |     |
|                                       *     |
|                                       |     |
|                                       |     |
|                                       M     |
|                                             |
+---------------------------------------------+