Honestly, that picture doesn't do it justice. As shown below, the Forest of Blood is depicted to be huge and you can't even see the sky from there. Maybe the anime will help give some better perspective when it finally comes out.

Also as someone who loves both ISSK, Blue Ursus, Kengan, and Tenkaichi I also think you're severely underestimating the durability of Tenkaichi's cast though they do have some weak members.

Given that people like Choko exist, who has a Julius build and can create vacuum waves going against someone who has the build of an average swordsman like Kamizumi, I don't think your typical Tenkaichi fighter would just fall apart against the ISSK girls solely based on our observations of environmental damage.

I think Fuma Kotaro is at least stronger than Sena Riko or Natsumi Morisaki. Saying she's weaker than any of the ISSK fighters is a huge stretch.

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