For epic level I might throw a completely magic-less dungeon at them filled with Indiana Jones-type traps. The magic user types will start to run out of utility spells early as often they stock up on attack/bonus spells instead of 'pass wall'. Once they start taking serious damage from spiked logs rolling down narrow corridors the party cleric will start to run out of spells as well. They will rest, but don't give them any monsters for several days as they meander through empty halls full of invisible caltrops. Also, make it so none of the traps are activated by summon critters. Once they are chewed up pretty good and the cleric & wizard have less damage spells, throw a powerful lich + entourage with plenty of enhanced magic things that have turning resistance at them the next time they rest.
