Crazy idea, but this would be a rigid stone and mortar structure built without modern earthquake standards. We might be able to just Tesla the thing. Rig a banshee slayer to shake the object they're attached to with a broad spectrum and mount earmuffs and silence mines to do it quietly. If you want to get fancy you could measure the frequencies which come back to find the structure's resonance and even just one tuned to it might well be enough to inexplicably make it shake itself to rubble in what appears to be completely natural failures at its most fragile points.
This is a really cool idea but I'd be concerned that we don't have a good way of testing this before trying it. And testing onsite extends our presence time severely.
Perhaps an option we should be ready for if we find the bridge completely undefended, but not the default.
It also requires getting very close.
Ideally for this mission:
1. We have a reliable long-range sensor (what long range sensors do we have in leaf?) that can identify ninja presence around the bridge. We camp at significant height/distance from the bridge for a day or so of observation, to hopefully identify if there's a ninja guard and when they rotate. Buy some telescopes?
2. If we do not detect any ninja presence (and one expects that any guards will not only contain full-stealth types, so good odds to see something if there's a guarding team), we have a relaxed timeline; can descend and look for accident-like ways of bringing it down like the banshee slayers / other vibrating seal. Only Kagome and his handler (Hazou) need descend (though with expecation of backup if combat occurs) to limit capture risk.
3. If we detect ninja presence on ground but not in the air, we bomb the bridge from significant height. Issues: at night time, it might be difficult to judge accuracy at distance. At daytime, it's likely we'll be visible and can be targetted with long range jutsu, plus expect civilian casualties. Also, using skywalkers for this is basically signing with 'yours faithfully, Leaf ninja'.
4. If we detect ninja presence in the air, we need to approach as standard infiltration mission - approach on ground (perhaps tunneling? but expect to be detected), take out grounded guards, plant ridiculous amount of explosives, GTFO, run away on skywalkers. (btw what happens to skywalker seals left behind in midair? are they consumed or does a blank drop onto the ground?
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