I agree. They need spells that cause elemental damage across a lot of monsters, but costs 100 to 200 mana. I say elemental damage so that some monsters are resistant to it, forcing you to learn a different tactic.
One problem with this could be running laps of the woods and having 100 monsters following you, which are all killed by one spell. Maybe if it damaged all creatures within the range, doing a maximum of #### damage.
