The abilities of your heroes fall into certain categories: Physical, Fire, Water, Storm, Earth, Life and Decay. Most abilities that do these types of Damage have a small chance to add a stack of a damaging debuff, such as bleeding, burning, or static. The in-game weather has been reworked so that certain kinds of weather drastically increase or decrease the chance of adding stacks of damaging debuffs. Use the weather to your advantage! Be careful, though, because your enemies will do this too!