-This is a (BD style) magic wall. It gets activated for about 10 seconds by
-rocks or gems that fall on it. Rocks that fall through it become BD style
-diamonds, and gems that fall through it become BD style rocks. After it has
-stopped running, it cannot be activated again.
+This BD style magic wall converts rocks into diamonds and vice versa. Note that
+a magic wall can only be activated for some limited time. It can also turn mega
+rocks into nitro packs, nitro packs into mega rocks. Even flying diamonds and
+rocks pass them to be converted into each other, but they do that from bottom to
+up, of course.