D&D 4E D&D 4e: A Fun, Fast Game that will Eat Your Paycheck

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This sparks my curiosity. When you had a 750 session campaign, did you advance levels and gain experience by the books? If so, which did you have, a level 50 campaign or very little combat?

Well. A ten-year campaign by definition had to be done with a ruleset prior to 3e.

If we assume for argument's sake that the rule-set in question was AD&D 1e, then we note that saving throws and to-hit probabilities cease improving at level 19 for clerics, 17 for fighters, and 21 for magic-users and thieves. Assassins, monks, and druids cease advancing at all at level 15, 18, and 14-or-23. Hit points after name level are accruing at +3/level for fighters and paladins, +2/level for clerics,rangers, and thieves, and +1/level for magic-users and illusionists. Spell progressions cease at level 29 for clerics and magic-users, at 26th for illusionists, at 14th for druids, at 20th for paladins, and at 17th for rangers.

So, you know. Even assuming the same characters throughout (no character retirements and playing of heirs/henchmen/whatever in the same overall campaign, which was typical in earlier editions), characters who reach 10,000th level are merely going to have more hit points than 29th-level characters. With all the save-or-die effects, those hit points aren't going to be all that important . . . and nobody can be brought back from the dead more times than they had in original points of Constitution.