diff --git a/tools/merge_out.py b/tools/merge_out.py
index e6d8bc08..dcab4738 100644
--- a/tools/merge_out.py
+++ b/tools/merge_out.py
@@ -1,10 +1,9 @@
 import json
 from formatter import per_line_entries
 
-out_ids = []
-out_dupe_ids = []
-out_edited_added_ids = []
-atlas_ids = []
+out_ids = set()
+out_dupe_ids = set()
+atlas_ids = {}
 
 with open('temp_atlas.json', 'r', encoding='utf-8') as out_file:
 	out_json = json.loads(out_file.read())
@@ -12,30 +11,32 @@
 with open('../web/atlas.json', 'r', encoding='utf-8') as atlas_file:
 	atlas_json = json.loads(atlas_file.read())
 
-for entry in atlas_json:
-	atlas_ids.append(entry['id'])
+for i, entry in enumerate(atlas_json):
+	atlas_ids[entry['id']] = i
 
 for entry in out_json:
-	if (entry['id'] in out_ids):
+	if entry['id'] in out_ids:
 		print(f"Entry {entry['id']} has duplicates! Please resolve this conflict. This will be excluded from the merge.")
-		out_dupe_ids.append(entry['id'])
-	out_ids.append(entry['id'])
-	
+		out_dupe_ids.add(entry['id'])
+	out_ids.add(entry['id'])
+
 for entry in out_json:
 	if entry['id'] in out_dupe_ids:
 		continue
 
 	if 'edit' in entry and entry['edit']:
-		index = next((i for i, item in enumerate(atlas_json) if item["id"] == entry['id']), None)
+		assert entry['id'] in atlas_ids, "Edit failed! ID not found on Atlas."
+		index = atlas_ids[entry['id']]
 
 		assert index != None, "Edit failed! ID not found on Atlas."
 
 		print(f"Edited {atlas_json[index]['id']} with {entry['edit']}")
 
-		if 'edit' in entry: 
-			out_edited_added_ids.append(entry['edit'])
-			del entry['edit']
+		del entry['edit']
 		atlas_json[index] = entry
+	elif entry['id'] in atlas_ids:
+		print(f"Edited {entry['id']} manually.")
+		atlas_json[atlas_ids[entry['id']]] = entry
 	else:
 		print(f"Added {entry['id']}.")
 		atlas_json.append(entry)