diff --git a/data/extensions/aseprite-theme/theme.xml b/data/extensions/aseprite-theme/theme.xml
index c3dabae98..a2882bf5a 100644
--- a/data/extensions/aseprite-theme/theme.xml
+++ b/data/extensions/aseprite-theme/theme.xml
@@ -420,8 +420,8 @@
         <part id="outline_full_pixel" x="214" y="224" w="5" h="5" />
         <part id="tiles" x="144" y="208" w="6" h="6" />
         <part id="tiles_manual" x="150" y="208" w="6" h="6" />
-        <part id="tiles_semi" x="156" y="208" w="6" h="6" />
-        <part id="tiles_auto" x="162" y="208" w="6" h="6" />
+        <part id="tiles_auto" x="156" y="208" w="6" h="6" />
+        <part id="tiles_stack" x="162" y="208" w="6" h="6" />
     </parts>
     <styles>
         <style id="box" />
diff --git a/src/app/script/engine.cpp b/src/app/script/engine.cpp
index 413697378..e1a1949a4 100644
--- a/src/app/script/engine.cpp
+++ b/src/app/script/engine.cpp
@@ -350,8 +350,8 @@ Engine::Engine()
   lua_pushvalue(L, -1);
   lua_setglobal(L, "TilesetMode");
   setfield_integer(L, "MANUAL", TilesetMode::Manual);
-  setfield_integer(L, "SEMI", TilesetMode::Semi);
   setfield_integer(L, "AUTO", TilesetMode::Auto);
+  setfield_integer(L, "STACK", TilesetMode::Stack);
   lua_pop(L, 1);
 
   // Register classes/prototypes
diff --git a/src/app/tileset_mode.h b/src/app/tileset_mode.h
index 2d0e8867a..452def6ca 100644
--- a/src/app/tileset_mode.h
+++ b/src/app/tileset_mode.h
@@ -14,8 +14,8 @@ namespace app {
   // tilemap is edited.
   enum class TilesetMode {
     Manual,   // Modify existent tiles (don't create new ones)
-    Semi,     // Auto-generate new tiles if needed, edit existent ones
-    Auto,     // Auto-generate new and modified tiles
+    Auto,     // Add/remove tiles automatically when needed
+    Stack,    // Stack modified tiles as new ones
   };
 
 } // namespace app
diff --git a/src/app/ui/color_bar.cpp b/src/app/ui/color_bar.cpp
index 19c691289..01d91e845 100644
--- a/src/app/ui/color_bar.cpp
+++ b/src/app/ui/color_bar.cpp
@@ -165,7 +165,7 @@ ColorBar::ColorBar(int align, TooltipManager* tooltipManager)
   , m_lastButtons(kButtonLeft)
   , m_editMode(false)
   , m_tilesMode(false)
-  , m_tilesetMode(TilesetMode::Semi)
+  , m_tilesetMode(TilesetMode::Auto)
   , m_redrawTimer(250, this)
   , m_redrawAll(false)
   , m_implantChange(false)
@@ -182,12 +182,12 @@ ColorBar::ColorBar(int align, TooltipManager* tooltipManager)
   m_tilesButton.addItem(theme->parts.tiles());
 
   static_assert(0 == int(TilesetMode::Manual) &&
-                1 == int(TilesetMode::Semi) &&
-                2 == int(TilesetMode::Auto), "Tileset mode buttons doesn't match TilesetMode enum values");
+                1 == int(TilesetMode::Auto) &&
+                2 == int(TilesetMode::Stack), "Tileset mode buttons doesn't match TilesetMode enum values");
 
   m_tilesetModeButtons.addItem(theme->parts.tilesManual());
-  m_tilesetModeButtons.addItem(theme->parts.tilesSemi());
   m_tilesetModeButtons.addItem(theme->parts.tilesAuto());
+  m_tilesetModeButtons.addItem(theme->parts.tilesStack());
   setTilesetMode(m_tilesetMode);
 
   m_paletteView.setColumns(8);
@@ -1420,11 +1420,11 @@ void ColorBar::setupTooltips(TooltipManager* tooltipManager)
   tooltipManager->addTooltipFor(
     m_tilesButton.getItem(0), "Show/Hide Tileset", BOTTOM);
   tooltipManager->addTooltipFor(
-    m_tilesetModeButtons.getItem((int)TilesetMode::Manual), "Manual-mode: Modify existent tiles,\ndon't create new tiles automatically", BOTTOM);
+    m_tilesetModeButtons.getItem((int)TilesetMode::Manual), "Manual: Modify existent tiles,\ndon't create new tiles automatically", BOTTOM);
   tooltipManager->addTooltipFor(
-    m_tilesetModeButtons.getItem((int)TilesetMode::Semi), "Semi-mode: Modify and reuse existent tiles,\ncreate/delete tiles if needed/possible", BOTTOM);
+    m_tilesetModeButtons.getItem((int)TilesetMode::Auto), "Auto: Modify and reuse existent tiles,\ncreate/delete tiles if needed/possible", BOTTOM);
   tooltipManager->addTooltipFor(
-    m_tilesetModeButtons.getItem((int)TilesetMode::Auto), "Auto-mode: Don't modify existent tiles,\ngenerate new tiles automatically only", BOTTOM);
+    m_tilesetModeButtons.getItem((int)TilesetMode::Stack), "Stack: Don't modify existent tiles,\ngenerate and stack new tiles automatically", BOTTOM);
 }
 
 // static
diff --git a/src/app/util/cel_ops.cpp b/src/app/util/cel_ops.cpp
index da965aeb3..890f89465 100644
--- a/src/app/util/cel_ops.cpp
+++ b/src/app/util/cel_ops.cpp
@@ -407,7 +407,7 @@ void modify_tilemap_cel_region(
 
   // Autogenerate tiles
   if (tilesetMode == TilesetMode::Auto ||
-      tilesetMode == TilesetMode::Semi) {
+      tilesetMode == TilesetMode::Stack) {
     doc::TilesetHashTable hashImages; // TODO the hashImages should be inside the Tileset
     {
       // Add existent tiles in the hash table
@@ -451,7 +451,7 @@ void modify_tilemap_cel_region(
       const doc::tile_index ti = doc::tile_geti(t);
       const doc::ImageRef existenTileImage = tileset->get(ti);
 
-      if (tilesetMode == TilesetMode::Semi)
+      if (tilesetMode == TilesetMode::Auto)
         modifiedTileIndexes[ti] = true;
 
       const gfx::Rect tileInCanvasRc(grid.tileToCanvas(tilePt), tileSize);
@@ -465,7 +465,7 @@ void modify_tilemap_cel_region(
       if (it != hashImages.end()) {
         tileIndex = it->second; // TODO
 
-        if (tilesetMode == TilesetMode::Semi) {
+        if (tilesetMode == TilesetMode::Auto) {
           if (tileIndex >= 0 && tileIndex < modifiedTileIndexes.size())
             modifiedTileIndexes[tileIndex] = false;
         }
@@ -507,7 +507,7 @@ void modify_tilemap_cel_region(
     }
 
     // Remove unused tiles
-    if (tilesetMode == TilesetMode::Semi) {
+    if (tilesetMode == TilesetMode::Auto) {
       // TODO reuse tiles that will be removed in the algorithm above
       remove_unused_tiles_from_tileset(cmds, tileset, modifiedTileIndexes);
     }