diff --git a/api/packages/game_domain/lib/src/models/board_section.dart b/api/packages/game_domain/lib/src/models/board_section.dart
index 2580fcf1d..fba74ca0c 100644
--- a/api/packages/game_domain/lib/src/models/board_section.dart
+++ b/api/packages/game_domain/lib/src/models/board_section.dart
@@ -14,9 +14,9 @@ class BoardSection extends Equatable {
   const BoardSection({
     required this.id,
     required this.position,
-    required this.width,
-    required this.height,
+    required this.size,
     required this.words,
+    required this.borderWords,
   });
 
   /// {@macro board_section}
@@ -24,7 +24,9 @@ class BoardSection extends Equatable {
       _$BoardSectionFromJson(json);
 
   /// Unique identifier of board section.
-  @JsonKey()
+  ///
+  /// Intentionally left out of serialization to avoid redundancy.
+  @JsonKey(includeToJson: false)
   final String id;
 
   /// Position of the board section in the board. The origin is the top left.
@@ -32,17 +34,17 @@ class BoardSection extends Equatable {
   @PointConverter()
   final Point<int> position;
 
-  /// Width of the board section.
+  /// Size of the squared board section.
   @JsonKey()
-  final int width;
+  final int size;
 
-  /// Height of the board section.
+  /// The words that start in this board section.
   @JsonKey()
-  final int height;
+  final List<Word> words;
 
-  /// The words that are contained in this board section.
+  /// The words that end in this board section, but don't start in it.
   @JsonKey()
-  final List<Word> words;
+  final List<Word> borderWords;
 
   /// Returns a json representation from this instance.
   Map<String, dynamic> toJson() => _$BoardSectionToJson(this);
@@ -51,8 +53,8 @@ class BoardSection extends Equatable {
   List<Object?> get props => [
         id,
         position,
-        width,
-        height,
+        size,
         words,
+        borderWords,
       ];
 }
diff --git a/api/packages/game_domain/lib/src/models/board_section.g.dart b/api/packages/game_domain/lib/src/models/board_section.g.dart
index 6852544d9..a1730b2d6 100644
--- a/api/packages/game_domain/lib/src/models/board_section.g.dart
+++ b/api/packages/game_domain/lib/src/models/board_section.g.dart
@@ -10,18 +10,19 @@ BoardSection _$BoardSectionFromJson(Map<String, dynamic> json) => BoardSection(
       id: json['id'] as String,
       position: const PointConverter()
           .fromJson(json['position'] as Map<String, dynamic>),
-      width: json['width'] as int,
-      height: json['height'] as int,
+      size: json['size'] as int,
       words: (json['words'] as List<dynamic>)
           .map((e) => Word.fromJson(e as Map<String, dynamic>))
           .toList(),
+      borderWords: (json['borderWords'] as List<dynamic>)
+          .map((e) => Word.fromJson(e as Map<String, dynamic>))
+          .toList(),
     );
 
 Map<String, dynamic> _$BoardSectionToJson(BoardSection instance) =>
     <String, dynamic>{
-      'id': instance.id,
       'position': const PointConverter().toJson(instance.position),
-      'width': instance.width,
-      'height': instance.height,
+      'size': instance.size,
       'words': instance.words.map((e) => e.toJson()).toList(),
+      'borderWords': instance.borderWords.map((e) => e.toJson()).toList(),
     };