I just did a 2-man Chaotic Tristram and earned my Hellfire Torch charm (Thanks Jds66). It took some thinking and strategy, but it is possible. Here's what you need:
Characters:
Hammerdin (With Concentration)
Hammerdin (With Salvation)
Summoner Necromancer (With Lifetap)
The Strategy:
* Send for the Necro to go make Skeletons and summon a Clay Golem.
* Send him into the portal to go out and pull a boss. I recommend Mephisto because he has a nasty Conviction and has the lowest life.
* Let the Necro Teleport on top of him and cast Lifetap. Lifetap is to ensure your Skeletons leech life to stay alive.
* Have one Paladin use Concentration and one use Salavation. Salvation will cancel out the Conviction Mephisto has as you will take little damage. This ensures the Skeletons stay alive also.
* Have the Paladins hammer him away. He should die pathetically in 30 seconds to a minute.
* Once Mephisto is dead, move onto the next boss and use the same strategy.
Notes:
* You will not receive a charm until all bosses are dead. As like the Annihilus, only one drops!
* Each boss will summon different monsters to aide him. Diablo, however, will summon Venom Lords that are immune to ALL resistances besides Magical and Physical.
* Don't piss around with the minions. Most do very little damage to even be bothered with, but be careful to not be overwhelmed.
Using this strategy, you will never die, and rarely go below 50% life. Have fun!