I never thought too much of Lina (too inept to use chargers properly), but now in my latest game as warrior I've snuck into Kordar just to charge her batteries (

) and went back to Darion / Isles. I must say that the ice ball is so much fun. I don't often manage to get the ball rolling for major damage increase, but I've found it serves as a class A distractor for enemy troops. Just plant it in the midst of enemy ranks and they'll be virtually hypnotised by it, while your troops shoot away. Of course, this may not be viable on higher difficulty levels (playing on normal), but it's still heaps of fun.