Cave of fire

Hello Redshift!
Can anyone write a guide for the caves of fire please? I've got one key from the one side and opened a square room with a invisible way. Another door is locked, and I dont have the key. Please help
Can anyone write a guide for the caves of fire please? I've got one key from the one side and opened a square room with a invisible way. Another door is locked, and I dont have the key. Please help