thmyl ttbyq ROT-13: thmyl → guzly ttbyq → ggod? Wait, let's do properly:
synmana ROT-13: s→f, y→l, n→a, m→z, a→n, n→a, a→n → flaznan . thmyl ttbyq Cee synmana llayfwn
t(20) -5 = 15 (p) h(8) -5 = 3 (c) m(13) -5 = 8 (h) y(25) -5 = 20 (t) l(12) -5 = 7 (g) → pchtg ? No. thmyl ttbyq ROT-13: thmyl → guzly ttbyq → ggod
t(20) +11 = 31 → 5 (e) h(8) +11 = 19 (s) m(13) +11 = 24 (x) y(25) +11 = 36 → 10 (j) l(12) +11 = 23 (w) → esxjw — no. (ROT-5 backward = ROT-21) let's do properly: synmana ROT-13: s→f