[...Wow, way to be a huge downer, Hershel. The unfortunate part of it is, Sasuke could actually imagine it, too.

People kept being brought in whenever others were taken out for whatever reason. Zero clearly had no problems whatsoever securing new subjects. Even accounting for those who became ill or died, the experiment could go on indefinitely unless...]

...In that case, wouldn't it be safer to try to find Zero himself? I don't think he would leave a secret escape hatch anywhere we could access. If we could find Zero, we might be able to get access to the facility controls and free ourselves that way. Besides that, we could take him in ourselves and make sure he couldn't continue his "experiments" again somewhere else with new victims.