So. My first dungeon ever, I was doing search and rescue. You know how sometimes you tell kids to watch out for sharks in the pool? Well, there were sharks in this pool, and people were kidnapped to "islands" of pool concrete, you know the stuff I mean. The portal was in sight, and everyone could reach it! They just had to cross the sections of pool between the various "islands".
The catch? The dungeon was scaled down. It must've been a new one, because the "sharks" were about six inches long and the sections between "islands" were about three feet wide. By the time I'd gotten there, everyone but an elderly couple had jumped across the water, island to island while the sharks watched and glared. One guy got bit in the ankle and he stomped the shark to death with his other foot and finished the crossing anyway. It probably would have needed stitches if there hadn't been a convenient esper around. I carried a plywood plank island to island and walked the couple out. He felt like he had to pay me back somehow, so now I have the best macaroni and cheese recipe on the planet.
The core was an afterthought. It was sitting in the far corner of the pool, we smashed it hopscotched back home.