You get a small boost from taking you hand away from the wall when climbing so you can basically alternate mouse clicks very fast and that will make it seem like you are actually climbing instead of just continuously propelling your self up the wall
It would make the crypt missles slightly more usefull if when they decide to lap around one guy instead of hitting them that the person they are targeting slows down slightly (because that would be a natural reaction when a random magic missle starts flying around you in circles)
The end is where they decide to start launching a tactical nuke to try and kill all the zombies (and you) and you get a minute or so to get to the tunnel (at the end) to escape, needless to say the nuke doesnt work
But beating the game is possible
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