All games have bugs. In The Sims, some were left in to become features.

We asked senior producer Lyndsay Pearson to run down some of Electronic Arts’ developers’ favorite programming errors in the long-running life simulation game.

“There are definitely cases where we see things after the fact, unintended side effects of things we didn’t plan,” she said. Some are trashed immediately because they get in the way of gameplay. But others are intriguing, or funny, and if they work well enough, developers leave them in.

Take The Sims 3’s cheats that could, if used in a precise order, make curved structures like arches or curved walls, she said. “People were able to use them to craft these really cool, much more organic shapes. We never thought to try that. That was a case of seeing it after the fact.”

In many cases, they rely on the users who discover the bugs to help them figure out how they work. For the arched walls, there’s a whole series of videos that give you the instructions to make it happen, Pearson said. “We often have to do the homework ourselves to see, wow, how did they put that together. We build these amazing puzzle pieces, these crayons, and then we give them to people and they do things we never thought about.”

Some bugs, however, take developers a lot less work to discover. Here are some of Pearson and EA’s favorites — five that are still discoverable in-game, and two pretty darned funny ones that aren’t (for obvious reasons).

5. Ghosts in coats

(We don’t have a picture of an outdoor ghost, so here’s a nice video of indoor ghosts for you.)

“That’s one of those cases where something emerged from the different part of the code that we didn’t think about,” Pearson said. Programmers had put outdoor clothing into The Sims, without thinking about how it might affect the game’s afterlife.

“A ghost went out the door and switched into a park and we were like, ‘What!’ ” she said, laughing. “That’s something where someone sends a screenshot to our internal list and everyone laughs. But then a developer said, ‘That’s funny, we should keep that.’ We liked it, so we decided to leave it as is.”

4. Rooms that float

The Sims 4

Above: Sims innocently play in a pool under a floating room in The Sims 4.

Image Credit: Electronic Arts

As The Sims gave more and more complicated tools to players to create structures, the programming rules to control how they worked became more rigid as well.

“We have all these rules for how things are supposed to work in Build, so you don’t end up in a strange situation where you’re on floor 1 and the game thinks you’re on floor 2,” Pearson said. But that didn’t stop players from discovering that, if you did certain steps in exactly the right order, you could create perfectly functional floating rooms.

“We saw it, and said, that’s not going to work really well,” she said. “But the more we played with it, the more we realized it was working pretty well. It was a neat outcome that we preferred to leave and share with fans.”

3. Ahoy, matey: Is that a pirate on your head?

The Sims 4 bug

Above: Making your Sim’s head a giant cupcake wasn’t originally supposed to be a game option, for some reason.

Image Credit: Electronic Arts

The ability to plop ridiculous objects on your Sim’s head wasn’t really a bug; it was a joke, slipped into the game by a programmer for his own amusement. The size of the objects isn’t limited, so it can get pretty ridiculous: You can create what looks like a dinosaur, stomping around town, or a giant pirate ship in the bathtub.