You open the coffer in the corner of the room, as your master instructed. "You will find something... a mask," he said, moments prior. "It will help the gardens of the world to... recognize you as a friend..." And you can see how that might be the case, maybe. The wooden mask is shaped much like your master's metal face, though with the lights in vine-like symbols on the sides, instead of in the eyes. Being shaped like the face of your master, though, it won't fit over your protruding face, so instead you opt to wear it over the top of your head. Hopefully the gardens of the world will still recognize you that way.
As you don the mask, a point of green light appears on the wall near you. It traces out a rectangle, and the rock suddenly pulls back there, sliding away to reveal a staircase spiraling up through the stone. With one last look at your master, lying peacefully behind you, and that heavy feeling returning to your stomach, you climb up into the unknown...
Sunlight greets you as you emerge. This you had expected. You did not expect this new thing however, pressing at you, tugging, pulling. You cannot see it, yet it runs over you, almost seeming to bite through your sleeves. You find yourself atop a flat space of rock: next to you, a wide hole. Looking down, you see below the entire world as you had known it. To think, there was more than the sky up here the whole time? Your master had hinted about such things, you remember, but you had found them hard to imagine. There are yet more rock walls around, up here, but they are not enclosing, more like large teeth ringing around this place. Further unknown beckons in all directions: you decide to go...