} else if (this.map_mode == 'terrain') {
         for (const p in game.portals) {
             let coordinate = p.split(',')
-            map_lines_split[coordinate[0]][coordinate[1]] = 'P ';
+            let original = map_lines_split[coordinate[0]][coordinate[1]];
+            map_lines_split[coordinate[0]][coordinate[1]] = original[0] + 'P';
         }
         let used_positions = [];
         for (const thing_id in game.things) {
 
                     map_lines_split[p.y][p.x] = 'A '
             elif self.map_mode == 'terrain':
                 for p in self.game.portals.keys():
-                    map_lines_split[p.y][p.x] = 'P '
+                    original = map_lines_split[p.y][p.x]
+                    map_lines_split[p.y][p.x] = original[0] + 'P'
                 used_positions = []
                 for t in self.game.things:
                     symbol = self.game.thing_types[t.type_]