The group gathers and rolls a ten sided dice to determine who will be the DM for that session. After the dm is selected the DM rolls 2d12 to determine random level for the player characters. Based on the starting level, the dm begins to plan encounters and setting for the sessions settings. Upon which campaign world, restrictions in class, magic items, funds available etc. At this point the DM should set down any house rulings that he wants to use or simply use the rules as written. One thing everyone taking part in the event should agree on is that the final call on anything is left solely to the DM of that event.
In some situations such as the group has access to the entire library, it must be left up to the DM to approve which books will be allowed, with some creativity new combinations of the core classes might be tested during the challenge. The DM has final say in all matters concerning characters allowed during the session.
The DM should be very careful about the CR rating for each encounter. While the current CR rating used may not be ideal, it does give a good test for the player characters and the DM should use all the abilities each monster has, it is after all a challenge for the DM and the players alike. A certain degree of care should be given each challenge, making each monster interesting and the whole of the challenge memorable. The idea is not to gain a total party kill, although that is a very likely event, at least the way my group plays it. The whole of the challenge is to get players to look at all their options and not get stuck into a situation where, player A is always the fighter, player B is always the cleric, etc. It requires that Player A can be a warrior but this time he is playing something a bit different, perhaps a Psychic Warrior or a Paladin this time around. Keeping the game interesting and enhancing aspects of the role playing side of the game as well as the combat encounters. It can make for a far more interesting game.
The need for balance in a game session is important for a number of reasons. Knowing that each of the Iron DM Challenges are a onetime event, some DM’s might be tempted to increase the challenge rating beyond the capabilities of the party and resulting in a TPK, (total party kill) the DM should do all that he can to refrain from this tactic, just because you can does not mean that you should. These brief rules are only a suggestion on how one can do a Iron DM Challenge, it is the intent of the IDMC to help players and DM’s look beyond the whole hack and slash methodology and find other ways of handling a given situation, it is also meant to help players look beyond their standard choices to other options and other classes so that they might better understand the strengths and weaknesses of other players in the game.