Currently I'm trying to make a new gamemode but I want the wool that I create with this command:
/execute @e[type=Snowball] ~ ~ ~ /fill ~1 ~1 ~1 ~-1 ~-1 ~-1 wool 5 replace barrier 0
...to disappear after 5 seconds. How can I do that? Also I was wondering if it is possible to change the color of wool when you enter a certain area in a map. So that I can create areas that are themed with a certain color.