­Mountain (2011 if important) + Sunwing Eagle

4/5 flier. Make red. Huh.

Annoyingly; despite the vanillaness, can't be common. Too big, and red fliers are Dragons and pheonices and such.

Can't really be a 'nix; they always have powers. So do most dragons, but we can have a wyvern I think.

About the only way I can make this interesting is my preference for putting vanillaness in the type-line.

Cost... eh, we'll do a non-aggressive cmc 5.

It wouldn't be groundbreaking / unheard of to have this at common: Scion of Ugin, Riverwheel Aerialists, and the recent Reaper of Night (that undoubtedly has a red-flag though).

In red? Red doesn't get common flyers.

Red has two common flyers in Magic 2020 alone, with Daggersail Aeronaut and Goblin Bird-Grabber. Admittedly, the rule of thumb seems to be 'Red can have flying in common, but only if it comes with restrictions.'

Admittedly, I don't think I want to see the mana cost Wizards would think is fair for a red dragon in common without restrictions...

https://markrosewater.tumblr.com/post/156879267353/red-is-allowed-to-have-creatures-with-flying-for

Like I said, not unthinkable. Some nonconditional red examples would be Sparktongue Dragon, Dragon Hatchling, and Lightning Shrieker. Would it be a bit unusual? Certainly, but weirder cards have appeared under nwo at common (in red) such as the forementioned Shrieker.