The wizard studies you.
“Work with me? How ambitious.”

He thinks for a moment.
“You can’t work with my sister. I can’t leave her alone with a man I barely know.”

You explain that you know about the stones, but you still can’t understand their magic. You might also be able to help with physical work. Since you spawned in this world, your strength has increased, so perhaps you can be useful.

He studies you again.
“You can’t cast magic, but if you’re skilled with a sword, you are some kind of fighter.... You can help me study the dimensions. I can open a few portals, and you can guard them in case an imp or some other creature tries to enter this plane and interrupt my research.”

He looks over several parchments covered in unintelligible words and numbers before finally speaking again.
“Ok, let's test your power. I can open portals to Hell or the Abyss, but I have to concentrate on my research. If a creature tries to enter, you don’t need to fight it to the death. Just prevent it from entering my tower through the portal. Besides, the portals are small. The larger demons and devils can’t cross them, so it should be relatively easy.”

He gives you a choice. You can test your strength by guarding the portal to the Abyss or the portal to Hell.