Guild Wars 2

If a catapult (and probably any other siege) is set up at the verge of water at the inner gate (aka as close to water as possible), and it’s destroyed with the person manning it standing behind/by/on it (not in front of it), it is very likely they will end up under textures under water. It happens quite often at southern inner Bay, possibly works the same everywhere else.
While it’s possible to target something above, and see what’s going on inside, all attacks are ‘obstructed’ unless you swim up as much as possible and use PBAoE/AoE for splash damage; even then no NPCs/gates can be harmed, afaik.

There’s no way to exit the spot other than port out, often losing the medal for taking a keep.

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