I felt challenged when Owl said he couldn't find a mask that looked like an owl. I thought an upside-down Axon helmet looked pretty good, and it doubles as a battle helm. It even looks like he has a mouth.
I also gave him wing-blades instead of claws.
Owl:"You want a piece of me?!"
His talons and legs.
My favorite part of the MOC though is his tail! I havn't seen a tail on any other versions of Owl, so I think its quite special.
Owl:"Hey guys, I'm here!"
Cossy:"Finally, our group shot is complete!"
???:"FREEZE YOUR CHEESE!!!"
Cossy:"Not him too!..."