Very nice engine - Only issue being that there is a bug which is when you hit a block sometimes you die. Overall though, very nice work (I liked the transition after you die especially)

Well actually the line: Mouse mouse = getWorld().getObjects(Mouse.class).get(0); should be: Mouse mouse = (Mouse) getWorld().getObjects(Mouse.class).get(0); (Just realised after I posted >.<)

Is the cat's act method just (assuming the dot is Mouse.class): if(!getWorld().getObjects(Mouse.class).isEmpty()) { Mouse mouse = getWorld().getObjects(Mouse.class).get(0); setRotation((int)(180*Math.atan2(mouse.getY()-getY(), mouse.getX()-getX())/Math.PI)); } (Would check myself but for some reason I can't DL the source code)

The first attempt I had after I said that, I won! You might want to add a check in for if the person has won, and if so add a scoreboard with the time it took them to win, and then stop the game. Oh and a good thing to do might be to reduce the fire rate of the tank slightly, if only to make the game run smoother (I'm currently on my really bad laptop, which is probably the only reason I'm experiencing slow-downs).