Here's how the mechanic of the 10th puzzle works : (use this website to decode)
Pm hu hyyvd ohz hu lejshthapvu thyr haahjolk av pa, pa tlhuz aoha fvb tbza mvssvd aol hyyvdz vu aol apsl aoha'z ilpun wvpualk av, iba aoha fvb kvu'a zlslja aol apsl aoha'z ilpun wvpualk av.v