diff --git a/mkessler-fancythm.sty b/mkessler-fancythm.sty
index 1f10af5..299080e 100644
--- a/mkessler-fancythm.sty
+++ b/mkessler-fancythm.sty
@@ -467,6 +467,7 @@
 \declarebigtheorem{thmvioletmarginandfill}{notation}
 \declarebigtheorem[zuSatz][Addition to Theorem]{thmredmarginandfill}{additiontheorem}
 \declarebigtheorem[Hilfssatz(?)][Helper Theorem(?)]{thmredmarginandfill}{helpertheorem}
+\declarebigtheorem[Not so serious theorem][Not so serious theorem]{thmredmarginandfill}{notsoserioustheorem}
 
 %%%Environments that are not numbered by default (notation, question, example, remark etc) have two forms:
 % - normal form: won't be numbered unless 'numbersmallenvironments' is set