Go Around the Back of the Castle.

You think to yourself about it and it occurs to you that the safest way forward here is probably trying to get into this place from the back entrance, assuming there is one. You'll have a better chance of getting in undetected that way. You walk down the stone stairs, trying to keep out of sight of the castle windows by hugging the wall and ducking as needed. You still don't know for sure that the inhabitants of the castle are hostile but better safe then sorry. As you make your way to behind the castle you do see what looks to be a back door. It's a sturdy looking thing made out of well-lacquered dark wooden planks, with a black iron knocker and a small peephole in the top of it. As you examine it the sweltering heat of the magma sea makes itself even more apparent to you, you need to get going. You try the door but it appears to be locked. Looks like you'll need to find a way around that. You could try simply knocking on the door, although that somewhat defeats the purpose of going around the back, or you could try and find something to lockpick the door with. What do you do?