How is そこを used in this sentence?


I'm having a difficult time understanding why そこを is used in the following
sentence. I don't think that を is marking a direct object, but it also doesn't
seem to fit the usual 経過 or 起点 interpretations. I also can't tell for sure
what そこ is referring to. Is it referring to the place or the point in time or
something else? My best guess is that そこを as a whole means either something
like "at that point", "then" or "there".

>
> しかるに、先だってのＫ96─ＭＡＬ遺跡地区での戦いで、彼女は極めて多数の〈六番目の獣〉を破壊した。しかも、本来であれば地中で眠っていたはずのものまでが地上に出てきていた、
> **そこを** 殲滅した」
>
> 「クトリ……が？」
>
> 「地上の〈六番目の獣〉の数は、今、著しく減少している──全滅とまではいかずとも、再び空に侵攻を始めるまでには相当の時間がかかることだろう」




そこを is literally "at that" or "there" as you guess. It is the object of 殲滅した,
and refers to those beasts(?) appearing above the ground, or to be precise,
the place as the location of those beasts' appearance.

Similar examples:

  * 一瞬の隙を見つけてそこを攻撃した spot an unguarded moment and attacked there.
  * 彼は一週間ほど留守にしていた。そこを泥棒に狙われた。 He was away for a week, which was taken advantage of by a burglar.

These suggest that そこを can be used when it talks about some opportunity/chance
(and the verb is transitive).

* * *

先だっての is 先{せん}だっての which means "earlier".




そこを is literally "at that" or "there" as you guess. It is the object of 殲滅した,
and refers to those beasts(?) appearing above the ground, or to be precise,
the place as the location of those beasts' appearance.

Similar examples:

  * 一瞬の隙を見つけてそこを攻撃した spot an unguarded moment and attacked there.
  * 彼は一週間ほど留守にしていた。そこを泥棒に狙われた。 He was away for a week, which was taken advantage of by a burglar.

These suggest that そこを can be used when it talks about some opportunity/chance
(and the verb is transitive).

* * *

先だっての is 先{せん}だっての which means "earlier".

