diff --git a/app/Main.hs b/app/Main.hs
index 0321876..20d6f72 100644
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -7,52 +7,101 @@ import Data.List.NonEmpty (NonEmpty(..))
 import Data.List.NonEmpty qualified as NonEmpty
 import Data.Set qualified as Set
 import System.Environment ( getArgs )
+import Data.Map (Map)
+import Data.Map qualified as Map
 
 import Model
 import Rendering ( render )
 import Parser (parse)
 
 data Game = Game {
-  gameWorlds :: NonEmpty World,
-  gameFlat :: Bool
+  gameFlat :: Bool,
+  gameMode :: GameMode,
+  gameSelect :: Int
 }
 
+data GameMode
+  = MenuMode
+  | PlayMode (NonEmpty World)
+
 main :: IO ()
 main =
  do args <- getArgs
-    case args of
-      x:_ | Just w <- Map.lookup x worldList ->
-        bracket (mkVty =<< userConfig) shutdown \vty ->
+    bracket (mkVty =<< userConfig) shutdown \vty ->
+      case args of
+        x:_ | Just w <- Map.lookup x worldList ->
           loop vty Game {
-            gameWorlds = pure w,
-            gameFlat = True
+            gameMode = PlayMode (pure w),
+            gameFlat = True,
+            gameSelect = Map.findIndex x worldList
+
             }
-      _ ->
-       do putStrLn "Usage: parabox <worldname>"
-          putStrLn ""
-          putStrLn "Available worlds:"
-          mapM_ putStrLn (Map.keys worldList)
+        _ ->
+          loop vty Game {
+            gameMode = MenuMode,
+            gameFlat = True,
+            gameSelect = 0
+          }
 
 loop :: Vty -> Game -> IO ()
 loop vty game =
- do let world = NonEmpty.head (gameWorlds game)
-    update vty (render (gameFlat game) (NonEmpty.head (gameWorlds game)))
-    ev <- nextEvent vty
-    case ev of
-      EvKey key _modifier ->
-        case key of
-          KUp    -> loop vty game{ gameWorlds = NonEmpty.cons (move world (-1,0)) (gameWorlds game) }
-          KDown  -> loop vty game{ gameWorlds = NonEmpty.cons (move world (1,0) ) (gameWorlds game) }
-          KLeft  -> loop vty game{ gameWorlds = NonEmpty.cons (move world (0,-1)) (gameWorlds game) }
-          KRight -> loop vty game{ gameWorlds = NonEmpty.cons (move world (0,1) ) (gameWorlds game) }
-          KChar 'r' -> loop vty game{ gameWorlds = pure (NonEmpty.last (gameWorlds game)) }
-          KChar 'z'
-            | Just worlds <- NonEmpty.nonEmpty (NonEmpty.tail (gameWorlds game)) ->
-              loop vty game{ gameWorlds = worlds }
-          KEsc -> pure ()
-          KChar 'f' -> loop vty game{ gameFlat = not (gameFlat game) }
+  case gameMode game of
+    MenuMode ->
+     do let (a,b) = Map.splitAt (gameSelect game) worldList
+        bnds <- displayBounds (outputIface vty)
+        update vty (picForImage (renderMenu bnds a b))
+        ev <- nextEvent vty
+        case ev of
+          EvKey key _modifier ->
+            case key of
+              KEsc -> pure ()
+              KUp   | gameSelect game > 0 -> loop vty game{ gameSelect = gameSelect game - 1 }
+              KDown | gameSelect game + 1 < Map.size worldList -> loop vty game{ gameSelect = gameSelect game + 1 }
+              KEnter | Just (world,_) <- Map.minView b -> loop vty game{ gameMode = PlayMode (pure world) }
+              _ -> loop vty game
           _ -> loop vty game
-      _ -> loop vty game
+
+    PlayMode worlds ->
+     do let world = NonEmpty.head worlds
+        update vty (render (gameFlat game) (NonEmpty.head worlds))
+        ev <- nextEvent vty
+        case ev of
+          EvKey key _modifier ->
+            case key of
+              KUp    -> loop vty game{ gameMode = PlayMode (NonEmpty.cons (move world (-1,0)) worlds) }
+              KDown  -> loop vty game{ gameMode = PlayMode (NonEmpty.cons (move world (1,0) ) worlds) }
+              KLeft  -> loop vty game{ gameMode = PlayMode (NonEmpty.cons (move world (0,-1)) worlds) }
+              KRight -> loop vty game{ gameMode = PlayMode (NonEmpty.cons (move world (0,1) ) worlds) }
+              KChar 'm' -> loop vty game { gameMode = MenuMode }
+              KChar 'r' -> loop vty game{ gameMode = PlayMode (pure (NonEmpty.last worlds)) }
+              KChar 'z'
+                | Just worlds' <- NonEmpty.nonEmpty (NonEmpty.tail worlds) ->
+                  loop vty game{ gameMode = PlayMode worlds' }
+              KEsc -> pure ()
+              KChar 'f' -> loop vty game{ gameFlat = not (gameFlat game) }
+              _ -> loop vty game
+          _ -> loop vty game
+
+
+renderMenu :: DisplayRegion -> Map String World -> Map String World -> Image
+renderMenu (w,h) before after =
+  pad ((w - imageWidth menu) `div` 2) 0 0 0 menu
+  where
+    menu =
+      case Map.minViewWithKey after of
+        Nothing -> string defAttr "empty menu"
+        Just ((k,_),after') ->
+          let len1 = (h-1)`div`2 in
+          pad 0 (len1 - Map.size before) 0 0 (vertCat
+            [ string defAttr x
+              | x <- drop (Map.size before - len1) (Map.keys before)
+            ]) <->
+            string (defAttr `withBackColor` cyan `withForeColor` white) k
+            <->
+            vertCat
+            [ string defAttr x
+              | x <- drop (Map.size after' - h`div`2) (Map.keys after')
+            ]
 
 
 worldList :: Map.Map String World
@@ -63,6 +112,9 @@ worldList = Map.fromList
   , ("center13", center13)
   , ("clone11", clone11)
   , ("transfer14", transfer14)
+  , ("transfer20", transfer20)
+  , ("transfer26", transfer26)
+  , ("transfer27", transfer27)
   , ("open4", open4)
   , ("cycle10", cycle10)
   , ("player10", player10)
@@ -1267,4 +1319,213 @@ multiInfinite8 = parse
   \▓▓▓▓▓▓▓▓▓\n\
   \▓▓▓▓▓▓▓▓▓\n\
   \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n"
+
+
+transfer20 :: World
+transfer20 = parse
+  "player p\n\
+  \block t blue boring\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓t▓a▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block a blue interesting\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓   ▓   ▓\n\
+  \▓       ▓\n\
+  \▓  ABC  ▓\n\
+  \▓   p   ▓\n\
+  \▓  XYZ  ▓\n\
+  \▓       ▓\n\
+  \▓   ▓   ▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \link A C cyan\n\
+  \link B C cyan\n\
+  \block C cyan interesting\n\
+  \▓▓▓▓▓ ▓ ▓\n\
+  \▓▓▓▓▓   ▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \  ▓▓▓▓▓▓▓\n\
+  \▓ ▓▓▓▓▓▓▓\n\
+  \▓ ▓▓▓▓▓▓▓\n\
+  \▓ ▓▓▓▓▓=▓\n\
+  \▓ ▓▓▓▓▓ ▓\n\
+  \link X Z green\n\
+  \link Y Z green\n\
+  \block Z green interesting\n\
+  \▓ ▓ ▓▓▓▓▓\n\
+  \▓   ▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓   ▓▓▓\n\
+  \▓▓▓ ▓ ▓▓▓\n\
+  \block p magenta boring\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓ ▓▓▓ ▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n"
+
+transfer26 :: World
+transfer26 = parse
+  "player p\n\
+  \block t blue boring\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓t▓a▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block a blue interesting\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓     ▓▓\n\
+  \▓       ▓\n\
+  \▓ T x 1 ▓\n\
+  \▓       ▓\n\
+  \▓ p 3 2 ▓\n\
+  \▓       ▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block x yellow boring\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block 1 cyan interesting\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓ ▓▓\n\
+  \    ▓▓ ▓▓\n\
+  \    ▓▓ ▓▓\n\
+  \    ▓▓ ▓▓\n\
+  \▓▓▓▓▓▓ ▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block 2 cyan interesting\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓  ▓\n\
+  \    ▓▓▓ ▓\n\
+  \    ▓▓▓ ▓\n\
+  \    ▓▓ ▓▓\n\
+  \▓▓▓▓▓▓  ▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block 3 cyan interesting\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓  ▓▓▓▓▓▓\n\
+  \▓▓ ▓▓    \n\
+  \▓  ▓▓    \n\
+  \▓▓ ▓▓    \n\
+  \▓  ▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block T green interesting\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \         \n\
+  \▓▓▓ = ▓▓▓\n\
+  \▓▓▓   ▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block p magenta boring\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓ ▓▓▓ ▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n"
+
+transfer27 :: World
+transfer27 = parse
+  "player p\n\
+  \block t white boring\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓t▓ab▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \link A a blue\n\
+  \block a blue interesting\n\
+  \▓▓     y \n\
+  \▓▓       \n\
+  \▓▓       \n\
+  \▓        \n\
+  \▓B     p \n\
+  \▓        \n\
+  \▓▓       \n\
+  \▓▓       \n\
+  \▓▓     x \n\
+  \link B b red\n\
+  \block b red interesting\n\
+  \       ▓▓\n\
+  \       ▓▓\n\
+  \       ▓▓\n\
+  \        ▓\n\
+  \ =--   A▓\n\
+  \        ▓\n\
+  \       ▓▓\n\
+  \       ▓▓\n\
+  \       ▓▓\n\
+  \block x yellow boring\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block y yellow boring\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \block p magenta boring\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓ ▓▓▓ ▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
+  \▓▓▓▓▓▓▓▓▓\n\
   \▓▓▓▓▓▓▓▓▓\n"
\ No newline at end of file