A Keep the mimic
->Go Left->
Anyway, Keep and Layout.
TURNTURNTURN
You name the mimic Matt, for now. You'll get 'em next time, Matt.
There's an interesting thing about being a Fractal Dungeon. At a glance, you'd think changing your entire layout would have an infinite cost- after all, you go on forever. However, Zeno will tell you that's not quite how things pan out. Which is fortunate, because it would kinda suck to be a featureless corridor forever.
With only a faint rumbling heard outside, your interior shifts. Irregularly spaced corners (all 90 degrees) are created- no junctions, for now. Every so often, the walls recede to create alcoves (half as deep as the corridor is wide)- useful for hypothetical monsters to hide in, perhaps. There's no decor, no variation to alcove size or corner angle, but hey- better than a straight corridor.
You wait around for a week, twiddling your metaphorical thumbs, before someone approaches you again. Adventurers, party of three. It appears the same mage is back, but with different companions: a second mage, and a moderately armoured one wielding twin axes. The axe-wielder seems disinterested in your dramatic entrance, but the second mage shares the first's curiosity. They spend some time standing just outside of you, examining the carvings on the pillars. Wafts of their curiosity and excitement reach you, but only enough to make you hungry. Or, well, the dungeon equivalent of hungry.
Eventually they enter, the axe wielder moving ahead. They soon reach a corner, which causes the first mage to exude a large quantity of excitement. He explains to his companions that there was definitely no corner here before, and that this proves this dungeon is in an infantile state. The second mage seems intrigued by the suggestion, and when she mentions the possibility of a poorly-defended dungeon core at the end of the dungeon, the axe-wielder becomes interested as well. They seem to think that you cannot be that deep at such a young age, and that your 'boss' is likely weak- yet your core may be very valuable.
Joke's on them, of course. You have no end, no boss, and no core. But they don't need to know that.
They agree to delve deeper, in search of the fictional finale. They soon encounter Matt... who doesn't achieve anything this time either, taking a handful of axe blows before collapsing. However, their greed, excitement, anticipation- it's a far more delicious meal than your previous fare. You could spice things up for them if you wanted to...
A: Throw a horde of weak monsters at them.
B: Throw one moderately strong monster at them.
C: Block their path with a confounding puzzle.
D: Place a modest artifact in an alcove.
(Or something else)