Thank you for kind words about box, I can add pulling action to player, but don't want to player must think about every action he make, if mistake was made, there is a restart button it will restart each level from the beginig and first level was made easy way, level is very simple and easy to finish, because player just getting started with game, thats why the turrent is not that dangerous I've made turrent that can aim in any directions, so if alien get too clouse he'll get shoot any way, also there are a simple bots that patrol some areas, and shoot alien if he is visible and so on, I just didn't use all them in the first level it shows only 60 % of all available functions of game I'm happy to hear that you liked my game about the frame rate, I'm working on very weak notebook, thats why the I care about frame rate and I'm trying to get it as high as it is possible. Thank you for advice about doors, I'll do my best and for thouse how make himself foundator of changing gravity idea, I took it from game vvvvvv. You can search for it. It's really great retro-style platformer.