LOL the elementals are a problem playing two warriors in hardcore mode (twice as many elementals). After that anything else seemed easy.
As with most enemies, the hammer spell is a real crowd killer <smile> if you have a mage in your team. Does nice damage and paralyzes any enemies near where it falls most of the time (enemies occasionally resist paralysis).
With two warriors you just need to run up and pound the darn thing till it dies, keeping a close eye on your health bar. When the ground starts shaking health goes down fast from that earthquake spell so you may need to suck down a potion every round. If a second elelmental is nearby casting you need to either run away fast of just take the damage and tough it out. The space bar is your friend.
By hitting pause constantly to stop the action, having lots of potions (the battlefield merchants restock nicely now), and having gained a level or two in the act 2 BFs before heading south I don't recall ever having anyone actually killed by the elementals since my first game when I was <blush> careless.