like a gryffin or pegasus. i wonder how you encounter them however.... maybe a a adult dragon who flew far away by accident is lost and you have to find a way to get it back? and afterwards you would get a faster way to travel and or the dragon... but for pegasus maybe you could get grabbed by a unholy demon and a pegasus saves you? maybe some kind of demon was going for some random human to use for some purpose and maybe you can resist the pegasus and get a new ending? eh speculations but dragons and other flying mounts would be fun.