They both play together so appropriately, there are frequent pauses, no one is being hurt so there is no yelping, since they play together a lot they only use abbreviated play bows, and all the growls and other noises are simply in play. I suppose someone who wasn't used to watching dogs play would assume they are fighting but I've watched enough dogs at play that I can usually tell when it starts going beyond play. Once early on, when Finna hadn't been here very long, I stopped their game because I saw Finna's hackles coming up. That's the only time I've ever seen things start to head toward inappropriate and after I stopped the game for a minute her hackles relaxed and Ranger went after her again; several laps around the yard later they were tired and happy dogs lounging in the grass panting side by side.
Ranger tends to be lazy and exert just enough effort to accomplish his goals. In general play he's fast but Finna is faster. What Finna didn't know for a long time is that Ranger has two more gears beyond where he usually plays with her. He has what we call putting it into gear where he really moves and what we refer to as going to afterburners where he flies. Finna likes it when he puts it into gear because that's a real challenge for her. The first time he went to afterburners it blew her mind because he can literally run circles around her when he does that. I suspect that if we ever get her unwound enough that she's not carrying any tension in her hips she'll be a challenge for Ranger even when he's gone to afterburners but for now there's no way she can keep up at that speed.
In my years of watching Ranger play with his pals and now watching him play with Finna I've noticed an interesting thing. Ranger often takes advantage of the tendency for dogs being chased to look back to see if the other dog is gaining on them. He used this on Finna the other day. He's chasing her and she's fleeing at top speed. Ranger peels off and angles to cut her off just as Finna looks back to see how close he's getting. Finna ploughs into his shoulder and looks astonished--he was behind her, what on earth is he doing blocking her way, how can he be in two places at once. Since Finna is really smart it didn't take her long to figure out what it is that he does and to try it herself. Except Ranger never looks back. As a result he sees what she's doing and rather than plough into her he leaps over her. He's able to physically block her in a race game because she'll look back but she can't block him because he doesn't look back.
Finna is roughly half Ranger's size and she's developed one form of attack that Ranger hasn't figured out how to counter yet. Finna will lower her head, drop her shoulders a little and run underneath Ranger. She's not quite tall enough to high center him when she stands back up underneath him but she is tall enough to make him have to dance to get off of her. Sometimes she'll zoom back and forth underneath Ranger's belly and I wonder if she's enjoying the sensation of being petted with a furry blanket.
There is no doubt in my mind that Ranger is the higher status dog at our house but the confidence that makes him so high status also allows him to assume submissive postures with no loss of status. Finna is always thrilled when she manages to knock Ranger to the ground although watching what I see is Ranger letting her knock him down. She loves getting him on the ground and chewing on his ruff and on his front legs. Ranger lets her wear herself out doing this then as she gets tired he'll leap up and take off after her. When Ranger wants to take Finna somewhere he'll take the side of her face in his teeth and lead her around.
Here's a bit of video of Finna and Ranger at play. Of course I would film this on a day when all my deck furniture is in the front yard for pressure washing and the dogs would insist on wrestling in the dirt. I left the audio as recorded so you can hear the play growls.