Back around the time Wrath of the Lich King launched, a fan site ran a "Design a Raid Encounter" contest. Since I had gotten through a good portion of the first tier of raid content by then, I figured that I had all kinds of wonderful ideas and took my pen to paper. I conjured up an encounter with the Titan's personal blacksmith as a one-off raid like Sartharion or Malygos. I scribbled room layouts on scraps of paper I had at my desk and thought up some particularly nasty mechanics that involved managing stacking buffs and debuffs based around molten slag. To top things off, I gave the boss a few construct adds that would be activated at certain health percentages in order to try to prevent straight burns.
A few months later, I was in Ulduar and saw Ignis with his golem adds, and I was hit with a wave of déjà vu. A similar situation arose when I first saw how Karsh Steelbender's fight went down. Did I channel some sort of developer mojo, or was this some sort of crazy coincidence?
I'd like to think that after playing the game as long as I have, as well as an additional 10 or so years of pen-and-paper RPGs, I'm bound to come to some of the same conclusions as the developers. I'm certain that I'm not the only one who's had his flights of fancy materialize in game content and that it will happen again.
What have you seen pulled from your imagination end up in game?