diff --git a/build/timestamps.txt b/build/timestamps.txt
index 2b38dd8a..19574663 100644
--- a/build/timestamps.txt
+++ b/build/timestamps.txt
@@ -630,6 +630,8 @@ fonts/times.8ital 197812032243.07
 fonts/times.8rom 197812032234.30
 fonts/times.9rom 197811111740.30
 fonts/tr14.kst 198301012313.02
+games/advent.f4 197703110000.00
+games/advent.dat 197703110000.00
 games/eliza.fasl 197709051143.18
 games/go1.fasl 197802050230.08
 games/go2.fasl 197802050231.20