The mtn_portal_story.rar file you have requested: Maps Levels Missions / Portal: MTN Portal Story Map v1.0 - 18.41mb is not available. Perhaps try browsing all files for the game Portal and upload any files you want to share or are missing. This is the only information we could locate:
This is a Portal Story that i have made just for fun. Play through the maps, the level will change as you get to a certain point. The puzzles get harder as you move on.