Arctic Shatter needs improvement

[will0]

Arctic Shatter: Any enemy slain while frozen by the initial impact of Frost Bolt has a 20% chance to leave behind an ice patch that freezes other enemies that walk over.

Compare Arctic shatter to Nilbog pool, niblog produce even a bigger AA pool and 100% chance, I hope STS can give this upgrade 50-60% chance or 100% chance on charge with a bigger pool area.

As most mage don't use this skill upgrade it is not useful at all since it don't always happens with 20% chance only and doesn't do any damage even it does chance to create ice patch it is small and most mob dont walk over.