His veins have become distended, muscles tightened, the teeth grown a little like claws, and his face has become rough.
This sentence describes what changes in appearance have happened to a person visually.
In "muscles tightened", I omitted "his" and "have". Instead of saying "his teeth have grown", I wrote "the teeth grown". In the last part, I added "has", I didn't omit it.
The reason wrote like this is to make it simple and easy to read. The reason I omitted in the two middle part is that I felt it okay to omit there, I think it still makes sense. I didn't omit the "has" in the last part because I felt, it didn't sound right to me without "has".
I'm not sure whether this kind writing is valid and acceptable in English.
I could have written the above sentence as below, but I didn't.
His veins have become distended, his muscles have tightened, his teeth have grown a little like claws, and his face has become rough.