...or to group with people of a lower level.
Players should have the option of lowering their level to +2 over the level of the dungeon in order to play it, as either a fleshed-out version of one of the hirelings or as one of a list of characters (or friendly monsters) generated specifically for the particular dungeon you are trying to conquer.
These toons receive regular XP for their controller but no treasure.
Example 1: Stu is level 10. His friend Arty is 25th level. They want to group, but neither has a toon in the level range. Stu enters the dungeon and Arty enters afterwards as Murphles, a pre-generated character that is a level 10 wizard with a standard loadout of spells. After the adventure ends, the XP earned by Murphles is applied to Arty's XP total.
Example 2: Arty is bored and wants to solo, but he doesn't want to play the dungeons at his level because he's bored of them. He enters a Splinterskull as Gursh, a Hobgoblin Shaman that levels as he proceeds through the adventure arc. After each adventure, XP is tallied toward Arty's XP total, but no treasure is gained. The end reward for the arc is still available though.
What do you think?