Four different Rottweilers were used to portray the dog. Special non-toxic makeup was used. The dog's face was shaved in spots and a vegetable based bloody substance applied to the shaved areas.
The xenomorph in this movie is referred to as "the dragon" by the character Golic and this is repeated by Ripley when she asks to question him. Some fandom have dubbed this movie's xenomorph "the dragon" for that reason. In that sense, a dragon does die in this movie.
Newt is dead at the beginning, you see her briefly while they are reporting the deaths, there's also the scene in the morgue, and an autopsy of her body which can be disturbing to watch.
A Black man is a self-admitted r*pist and murderer of women. It’s likely that the prisoners represent AIDS victims. As a result, the film seems to conflate being queer with being a r*pist or murderer. The prisoners are also shown trying to atone for their sins through prayer, which could have homophobic connotations in this context (“pray the gay away”).