There’s a lot that happened during The Walking Dead‘s six year time jump, but one of the biggest remaining mysteries is how Michonne and Daryl received those “X” scars on their backs. Michonne’s scar was first revealed in “Who Are You Now,” and this week’s episode, “Stradivarius,” made sure to include a shot of Daryl’s back, this time revealing that, among his many scars, he too has a similar “X” on his lower back.

Following the dramatic departure of Rick Grimes, The Walking Dead did something of a soft reboot when it jumped ahead six years in the future. This not only aged up some characters – most notably, Judith Grimes – but it also introduced some big changes for other characters. Michonne has grown more paranoid, Daryl lives alone in the woods, Carol remains at the Kingdom (which is falling in to disrepair), and Maggie has departed from Hilltop.

The communities are now more divided than ever, but it isn’t exactly clear if it was Rick’s “death” that broke them up or something else. The scars on Michonne and Daryl’s backs might be a clue, hinting at some traumatic encounter that was enough turn the communities more inward, hiding behind their walls. So how did Michonne and Daryl get those scars?

The Scars Could Be From An Injury or Wound

In order to receive those scars, it’s possible that both Michonne and Daryl were injured, perhaps even attacked and wounded. During the council meeting in last week’s episode, “Who Are You Now,” Michonne implies they have faced threats in the last six years, so her and Daryl being wounded is a very real possibility.

Then again, it’s difficult to overlook not only how similar Michonne and Daryl’s scars appear – almost identical, in both appearance and location – but how precise they are, almost surgical. This would suggest these scars aren’t from something random like an injury or wound, but are the result of a more exact technique.

The Scars Could Be From An Incision

Instead of Michonne and Daryl’s scars being from some old injury or wound, the “Xs” might be marks left from an incision. The scars appear very deliberate, which does suggest they were caused by a precise action like purposefully cutting the skin. What that doesn’t explain, however, is why Michonne and Daryl would each have one of these incision scars.

If the scars are from the skin being cut, it’s obvious that neither of them could have cut the “Xs” themselves given where they are on their bodies. This would mean someone else had to cut the “Xs”, and while it isn’t impossible these are surgical scars, it’s far more likely they were cuts made to mark Michonne and Daryl. Just who would do that remains a mystery, but it’s hard to imagine a scenario in where they’re given these marks for a good reason.

The Scars Could Be A Marking or Brand

Michonne and Daryl having almost identical scars in practically the same spots on their bodies suggests they’ve been given some kind of marking or brand. It’s even possible that the “Xs” aren’t from a cut or incision, but are a burned brand on the skin. However they received their marks, something obviously happened during the six year time jump which led to Michonne and Daryl being branded and it wasn’t anything good.

Why they were given the “Xs” is the mystery, of course, and one showrunner Angela Kang has promised will be revealed at some point in the future, though it’s certainly something they will address. Maybe they were captured, and as prisoners they were marked? Michonne was quick to recognize Magna’s prison tattoo, perhaps this is why. Or maybe some new enemy was marking their prey, and Michonne and Daryl were the lucky two who survived? A serial killer of sorts could explain why the communities began mistrusting each other.

Next week’s episode is the midseason finale, so it’s unlikely there will be a whole lot more revealed about these scars in just one episode. In which case, expect Michonne and Daryl’s scars to be further explored when The Walking Dead returns from hiatus next year. The Whisperers, a new enemy this season, will also be more fully introduced after the hiatus, and it might be that the reason for the “X” scars will be explained alongside the fight against the Whisperers. It’d make sense for Michonne and Daryl to recall the last crazy dangerous foe they fought while in conflict with another, and it might even mean getting flashbacks to those years skipped in the time jump.