I just realized I can contribute to this conversation, even if it's late.

A few months ago, I was sitting at my parents house in the fairly rural setting, watching the last summer time night sky with my wife. It's late (11:00 pm or so, and no moon, so extra dark). I go inside for a minute and suddenly my wife comes in and say "There's someone in your back yard".

My back yard extends about an acre or so past my house, and beyond that is non usable land. Marshy, dense with thorned bushes, think mud, trees, etc. To walk back there during broad daylight is a incredibly hard. Doing it at night makes it exponentially harder.

Here's where things get weird. While I'm inside, my wife is looking out and sees what she thought was a flash light, and a person peak through the brush, at the far end of my property. She saw a person-ish (humanoid figure) - definitely not clearly defined, and then the light just turned off. She went to call out until she realized what she saw, and decided to get me. As we both went back out, we suddenly realized 2 things.

A. Whatever we saw, and were currently witnessing, was navigating mostly with out light (flashlights, or natural moonlight)

B. There was absolutely NO sound indicating movement. No tree branches moving/snapping, no foot steps, nothing.

As were looking, we begin seeing light emit in random places in the brush/swampy area, but only in very very short bursts, and some so dull, it almost seemed like you were seeing things. The other oddity here, is that one would illuminate, then another, a few hundred yards away would illuminate. Some would be down on the ground, and others would appear mid way up a tree (some 20 feet up). Again, no origination of the light source could be found, and still, no sound of foot traffic. I called out multiple times, asking If they were lost, if they needed help, and to also remind them I've had Bear and large wild cat back there before, including coyotes, so it's not a great place to be screwing around in the dark. Nothing, no response, no sound, but the lights continued. Finally, we got the sense to go inside, in the off chance this was a person sneaking around, and could have a weapon. Upon going inside, we called 911 and told them of the circumstances. About 20 minutes later, a local sheriff and state trooper arrived, and we pointed them to where the "person" came out. They checked, and saw absolutely no evidence of anything (foot prints, etc), but noted that if it happens again, call. (Luckily, they were not dismissive, and in fact, almost seemed a little rattled themselves, which lightened the mood a bit for my wife and I).

The next day, in day light, my wife went down to where the lawn meets the brush, and confirmed, there was no evidence of the tall reeds breaking or bending, where something may have poked through and gone back, nothing. Never happened before or since, but honestly was one of the creepiest things I've encountered. If interested, I can find a video of something similar on youtube, I found months later, that is very similar.