bah.... I like that entangling roots... there is no move that allows you to attack a unit while preventing it to move, not only that, the move does damage on it's own. Focusing it's power on one unit, it comes incredibly handy when you want to destroy a hero in retreat or even in combat.
Not to kick the chain lightening in the pills... that would be my second pick, only because you can't really focus where the damage is done. nothing says that you'll actually hit the unit you want to unless you target it specifically.