The central question in this paper is whether anthropogenic mass extinction is ethically problematic above and beyond the sum of extinctions involved. The point of asking this question is not to determine the ethical status of anthropogenic massive extinction, which is clearly ethical horrendous. It is to see if - as is the case with interrogating the wrongness and badness of extinction - answering it illuminates something about the value of what is being lost and sharpens the considerations that substantiate (...) the view; and, if so, whether that might be useful in the context of evaluating mooted approaches to mitigating or adapting to it. The view defended is that massive extinction driven by undermining the conditions that make life forms possible for diverse and higher taxonomic groups constitutes a planetary shift, a phase change, different in kind from merely accelerated anthropogenic change. Justified partiality to the current assemblages of species and biomes is grounded in human relationships, dependencies, histories, and connections with this particular planetary state. This partiality warrants recognizing the loss of this state of the planet - these biospheric conditions, species assemblages, and biomes - as bad, above and beyond the individual harms and species losses involved. This account explains and substantiates why a mass extinction is worse than an equal number of extinctions spread over multiple systems or planets, all other things being equal. This account also provides reason not to embrace the anthropocene or embark on a synthetic age. (shrink)