1. if you upgrade to a stronger weapon in a co_ game can you go back to a weaker one, ex. gernade launcher to machine gun
2. if you buy the welder do you stay as a welder for the rest of the game, if yes how do you fight (never tried buying it before)
3. on aliesn when you upgrade to lets say a gorge from a skulk are you stuck as a gorge for the rest of the game or can you upgrade further and further
i will add more as i think of them