5 Things You Didn't Know About Sunday's Episode Of 'The Walking Dead'

Mini-spoilers ahead.

AMC released a behind-the-scenes video from Sunday's episode of "The Walking Dead" showing how it was put together.

In addition to seeing how the zombie prison scene was filmed, we learned a few cool tidbits about the episode.

No big spoilers here from last night's episode, but if you haven't watched, you may want to stay clear.

1. Danai Gurira (Michonne) is really riding the horse.

She doesn't need a body double. Gurira told the crew she was familiar with horses. She says she rode them a little when she was younger.

2. The name of Michonne's horse is Chase.

Gurira hand selected the horse from a few others for the show.

3. The crew originally wanted to have a moat in front of the prison.

Executive producer Greg Nicotero says that became impossible because of quicksand found outside.

"I was so excited," said Nicotero. "The quicksand was not the friend I hoped it would be, but was the mortal enemy of the production design because now we had to scrap that whole idea of the moat."

4. The gate and wooden spikes were inspired by Morgan from last season.

If you recall, Morgan had Rick's hometown rigged with booby traps.

5. The "super flu" terrorizing the prison is inspired by a real life influenza.

Nicotero revealed on "The Walking Dead" after show "Talking Dead" that the virus spreading around the cell block was influenced by The Great Pandemic of 1918 to 1919 that killed an estimated 30 to 50 million people worldwide.