The reason being is that there just is not enough other buttons around the arrow keys for turrets/skills/grenades as a lot of keyboards have different layouts for the keys around the arrow keys. E.g. laptop and stuff. Some keyboards don't have numpads so we couldn't use those. Its gets difficult.
 "SAS: Zombie Assault 4"){kind=icon}
 "A Dance of Fire and Ice"){kind=icon}
The reason being is that there just is not enough other buttons around the arrow keys for turrets/skills/grenades as a lot of keyboards have different layouts for the keys around the arrow keys. E.g. laptop and stuff. Some keyboards don't have numpads so we couldn't use those. Its gets difficult.