Improving Blizzard mutator

Cold is the Void is a recent challenging mutation. Part of its difficulty came from not being able to take expansions because of Blizzard mutator. That is not inherently a bad thing. I enjoyed the change of not having two bases. However, the way Blizzard mutator is set up has some issues, and so I tried to come up with some improvements. My goal was to prevent blizzards from coming through expansions, and to get rid of the safe zones in front and behind the main base region. As it is, blizzards come from an angle specific to the map, check if the path intersects main base region, and if it's not the case, blizzards are spawned. No blizzard will come straight towards the main base and all travel in the same direction. This leads to no blizzards being in front and behind the main base.

The first iteration

At first I tried adjusting the angle in which blizzards come. I managed to make expansions safe and minimize safe zones, but it wasn't perfect.

The second iteration

The next version was a lot better. Blizzards spawn all along the left border of the map, but when they enter regions of the main base and expansion they became harmless. Their appearance changes, indicating they are not posing any threat.

The video is demonstrating this change in action. Safe zones in front and behind main bases are no more, and expansions are safe. It's easy to add any additional regions that are supposed to be safe or remove them (e.g. deny expansions again).

Here is the battlenet thread and the map file. Additionally, it would be a good idea to properly set up safe regions for expansions on all maps. There are problems with other environmental mutators on The Vermillion Problem, Miners Evacuation, Scythe of Amon, Chain of Ascension and Oblivion Express. Also, on Lock and Load the safe region doesn't cover the top-most expansion gas.

This change could significantly improve Blizzard mutator. Similar but easier solutions could work for other mutators that prevent players from expanding. I'm not against forcing players to stay on one base. But not all environmental mutators have to do that.