diff --git a/.gitignore b/.gitignore
index ff68d765..f0738211 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
-.venv
-__pycache__
-decompiled-*
-out
+.venv/
+__pycache__/
+decompiled-*/
+out/
+.DS_Store
diff --git a/.vscode/launch.json b/.vscode/launch.json
new file mode 100644
index 00000000..a6ed804b
--- /dev/null
+++ b/.vscode/launch.json
@@ -0,0 +1,13 @@
+{
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Build the Deltarune site",
+            "type": "debugpy",
+            "request": "launch",
+            "program": "build.py",
+            "console": "integratedTerminal",
+            "args": "deltarune"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/script.py b/script.py
index f8df625a..c17cef83 100755
--- a/script.py
+++ b/script.py
@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 import argparse
+import html
 import os
 import re
 import sys
@@ -18,7 +19,7 @@
 )
 
 
-def parse_text(text: str) -> str:
+def parse_text(text: str, is_format: bool) -> str:
     # Parse Undertale codes the same as Deltarune
     text = re.sub(r'\\\\', r'\\', text)
     # General text codes
@@ -42,6 +43,13 @@ def parse_text(text: str) -> str:
         '<span class="cc cc-close">Close Message</span>',
         text,
     )
+    if is_format:
+        # '~[x]': interpolated argument
+        text = re.sub(
+            r'~([1-9])',
+            r'<span class="cc cc-arg">Argument №\1<span>\1</span></span>',
+            text,
+        )
     # '\E[x]': emotion
     # '\M[x]': special, typically emotion on overworld sprite
     text = re.sub(
@@ -97,7 +105,7 @@ def highlight_text(matches: re.Match[str]) -> str:
         before_var='"',
         variable=matches[2],
         after_var=matches[3],
-        parsed_text=parse_text(matches[2]),
+        parsed_text=parse_text(matches[2], 'subloc' in matches[1]),
     )
 
 
@@ -106,7 +114,9 @@ def highlight_text_ch1(matches: re.Match[str], data: Data) -> str:
         before_var=matches[1],
         variable=matches[2],
         after_var=matches[3],
-        parsed_text=parse_text(data.get_localized_string_ch1(matches[2])),
+        parsed_text=parse_text(
+            data.get_localized_string_ch1(matches[2]),
+            False),
     )
 
 
@@ -232,21 +242,17 @@ def process_line(
 ) -> str:
     # Escape dangerous HTML characters.
     # This preserves strings like "THE LEGEND OF THIS WORLD.#<DELTARUNE.>"
-    line = re.sub(
-        r'(&|<)',
-        lambda matches: {'&': '&amp;', '<': '&lt;'}[matches[1]],
-        line,
-    )
+    line = html.escape(line, quote=False)
 
     # Highlight localized strings
     line = re.sub(
-        r'([A-Za-z0-9_]+loc\((?:\d+, )?)"((?:[^"\\]|\\.)+)(", "[a-z0-9_-]+")\)',  # noqa: E501
+        r'([a-z0-9_]+loc\((?:\d+, )?)"((?:[^"\\]|\\.)+)(", (?:.+, )?"[a-z0-9_-]+")\)',  # noqa: E501
         lambda matches: matches[1] + highlight_text(matches) + ')',
         line,
         flags=re.IGNORECASE,
     )
     line = re.sub(
-        r'(scr_(?:84_get_lang_string(?:_ch1)?|gettext)\(")([a-zA-Z0-9_-]+)("\))',  # noqa: E501
+        r'(scr_(?:84_get_lang_string(?:_ch1)?|gettext)\(")([a-z0-9_-]+)("\))',  # noqa: E501
         lambda matches: highlight_text_ch1(matches, data),
         line,
         flags=re.IGNORECASE,
@@ -259,7 +265,7 @@ def process_line(
         flags=re.IGNORECASE,
     )
     line = re.sub(
-        r'(room_goto\()([A-Za-z0-9_]+)',
+        r'(room_goto\()([a-z0-9_]+)',
         lambda matches: highlight_room(matches, data),
         line,
         flags=re.IGNORECASE,
@@ -272,7 +278,7 @@ def process_line(
     )
     # Link to functions and alarms
     line = re.sub(
-        r'(\b)(s?cr?_[a-zA-Z0-9_]+)\(',
+        r'(\b)(s?cr?_[a-z0-9_]+)\(',
         lambda matches: highlight_function(
             matches, script_name, text, data, resolve_references
         ),
diff --git a/static/main.css b/static/main.css
index 89722fef..e69c9cc1 100644
--- a/static/main.css
+++ b/static/main.css
@@ -23,6 +23,9 @@
 	--close-text-color: #fff;
 	--face-background-color: #252;
 	--face-text-color: #8c8;
+	--arg-background-color: #707;
+	--arg-text-color: #fff;
+	--arg-collapsed-text-color: #aaa;
 	--flag-not-found-text-color: #ec6;
 	--flag-found-text-color: #fd8;
 	--flag-found-background-color: black;
diff --git a/static/script.css b/static/script.css
index 450bab58..1091d0ec 100644
--- a/static/script.css
+++ b/static/script.css
@@ -111,6 +111,27 @@ pre:not(.funcCode), code, .hljs {
 	user-select: none;
 }
 
+.cc-arg {
+	background: var(--arg-background-color);
+	color: var(--arg-text-color);
+	user-select: none;
+}
+
+.cc-arg > span {
+	position: absolute;
+	right: 0;
+	bottom: 0.1em;
+	display: inline-block;
+	font-size: 70%;
+	color: var(--arg-collapsed-text-color);
+	text-indent: 0;
+	font-style: italic;
+}
+
+.cc-arg:hover > span {
+	display: none;
+}
+
 .cc-delay:before {
 	content: '\231b';
 	margin-right: 0.2em;
@@ -124,6 +145,10 @@ pre:not(.funcCode), code, .hljs {
 	content: '\239a';
 }
 
+.cc-arg:before {
+	content: '\2386';
+}
+
 .cc-color {
 	color: white;
 }
diff --git a/templates/highlight/text.html b/templates/highlight/text.html
index c61dfd78..4fd2c5e5 100644
--- a/templates/highlight/text.html
+++ b/templates/highlight/text.html
@@ -1 +1 @@
-<div class="langtext"><span class="skip-highlight">{{ parsed_text | safe }}</span><div class="langvar">{{ before_var }}{{ variable | safe }}{{ after_var }}</div></div>
+<div class="langtext"><span class="skip-highlight">{{ parsed_text | safe }}</span><div class="langvar">{{ before_var | safe }}{{ variable | safe }}{{ after_var | safe }}</div></div>