Warning: There are spoilers ahead for AMC's "The Walking Dead" season eight premiere, titled "Mercy.""The Walking Dead" finally went to war onSunday night's season eight premiere. After losing his way on season seven, viewers were treated to a no-nonsense Rick Grimes who may have executed his best plan to date, a giant walker herd stormingthe Sanctuary, and a few intriguing flash-forwards.Rightfully so, the100th episode of the series had a lot of nods to previous episodes, teases of what's to come, and one very special dedication that may not have caught your eye on a first watch.Keep reading to see everything you may have missed.Let's start with an easy one. We see an older, grayer Rick wake up near the episode's start.When this shot appeared in the season's first trailer many thought it confirmed a long-believed fan theory that the zombie apocalypse was taking place in Rick's head during a coma. That's not the case.It's a direct callback to the show's first episode.Everything from the way that Rick wakes up, to the focus on the flowers at his bedside could easily fool fans into considering the entire show may have been a crazy coma dream.Episode director Greg Nicotero told INSIDER we are seeing a "great, thriving community" in Alexandria at some point in the future.You can read more on what the mysterious flash-forward in the episode means here.The truck Carl drives has a familiar logo on it.See the rest of the story at Business Insider Click here to read full news..