Can you correctly drop auxiliary verbs in writing?

Question

While creatively writing, I found myself dropping an auxiliary verb (I believe?) in a description. The statement went: "He seemed to be a freak of nature, his mutilated feautures artificially altered, his parchment skin impossibly white."

Is this grammatically correct or should it be, "He seemed to be a freak of nature, his mutilated feautures were artificially altered, his parchment skin was impossibly white"?

To me, the second example doesn't really read right, but I honestly don't know whether or not the first one is correct. I couldn't really find an answer online, as I wasn't sure how to word my search (though it's probably better I ask here anyway, because I can show what it is that I'm writing). So, did I write this correctly, or should I word it differently; is it okay to drop auxiliary verbs? (Oh─ and is it 'while creatively writing' or 'while creative writing', haha?)

These may be stupid questions, but I'm a bit confused and could really use some quick help, so forgive me. ♡

Answer 1

Was and were are not auxiliaries in this context, but full verbs.

Your original text is perfectly good for writing, though it would be less common in spoken English. It contains two small clauses.

Your emended version with the verbs in is also grammatical, except that it is a run-on sentence. The commas need to be at least semicolons, if not full stops creating three separate sentences.