diff --git a/editor-extensions/vscode/syntaxes/grain.json b/editor-extensions/vscode/syntaxes/grain.json
index 998d1eb..c1eefd9 100644
--- a/editor-extensions/vscode/syntaxes/grain.json
+++ b/editor-extensions/vscode/syntaxes/grain.json
@@ -829,7 +829,11 @@
       "patterns": [
         {
           "name": "constant.character.escape.grain",
-          "match": "(\\\\\\d{1,3}|\\\\x[A-Fa-f0-9]{1,2}|\\\\u[A-Fa-f0-9]{4}|\\\\u\\{[A-Fa-f0-9]{1,6}\\}|\\\\.)"
+          "match": "(\\\\\\d{1,3}|\\\\x[A-Fa-f0-9]{1,2}|\\\\u[A-Fa-f0-9]{4}|\\\\u\\{[A-Fa-f0-9]{1,6}\\}|\\\\[bftvrn'\"\\\\])"
+        },
+        {
+          "name": "invalid.illegal.grain",
+          "match": "\\\\."
         }
       ]
     },