t↔g h↔s m↔n y↔b l↔o → gsnbo

Better: Try ROT13 on whole phrase:

But simpler: maybe but with kn2000 as hint: kn = xa in ROT13? kn in ROT13: k→x, n→a, so xa2000 . Not helpful. Step 10: Try ROT13 on kn2000 → xa2000 not meaningful.

ROT13 on thmyl : t→g, h→u, m→z, y→l, l→y → guzly (no).

Wait, if ly = in , then l→i (-3), y→n (-3) consistent! Yes! Because y (25) -3 = 22 = w? No — 25-3=22→w, not n. So not consistent. So ly can't be in with a fixed Caesar shift.

t (20) → q (17)? That doesn't look right because thmyl would start with q . But maybe ly = in works.

This looks like a simple substitution cipher (likely a shift cipher or a monoalphabetic cipher). Let me attempt to decode it.

The text: thmyl brnamj zf awrj ly alkybwrd kn2000 The word ly appears twice; in English, two-letter words are often is , it , in , on , at , my , by , to , of , etc. kn2000 looks like kn followed by a year, possibly in 2000 .