first choice

This is only an opinion
The following is only my opinion - how I would write the material given the choices.

1) I found a strange device (or "instrument").

2) It's a long ebony pen. ( is this right ? ). YES, it's O.K.

3) The struggle between duty and passion returned (possibly better than "came back").

4) "That vault / cellar / basement is full of biers / chests / coffers / coffins."

Vault is different from cellar or basement; these two can be the same. Biers, chests, coffers, and coffins are each dfferent in meaning, one from the other. They're not 100% interchangeable. So, one has to know exactly the meaning intended here.

5) The voice coming from inside ("the back of") my head ("neck") was screaming.

queer is more closely related to "wierd." queer also means gay no which has somehwat changed the feeling of the original word. odd would also be a good choice here.

struggle is like parties fighting over something...whereas strife is more just like conflict in general. so strife would not be the better choice.

the voice coming from inside the back of your head sounds like a horrible translation and doesn't make a whole lot of sense to me. screaming, shouting, and yelling are all pretty interchangeable except that screaming implies that it is a bit more frantic.

edit: also, hello again nav

Thanks Charli..Hi stuh