Serious Sam Revolution - Alpine Mists 2: Dusts of Ages pt.1 (Serious) 

Alpine Mists is a three-levels campaign set in different environments. This second level was well balanced and quite vary with the envinronments. Thanks to the creator RatBoy and to Emperor Longcat for republishing it
Steam's workshop page:
steamcommunity...
I've played this map in blind run at Serious difficulty. When you see the fades, it generally means that I've died there, or that I went back somewhere to pick up some stuff or that I've reloaded 'cause I let myself be hit too much in stupid ways