I posted a while ago about a lightning dragon and one of the answers was really interesting. The answer, in this case, is from Mr Adrian Colomitchi, it was very detailed, but I still had doubts with that vocabulary too sophisticated for me to understand, so to reach a greater number of people I decided to make a series of posts about my doubts.
Initially I was planning a dragon, but then I decided to switch to a bird and Mr Adrian's answer gave me one more reason for this change (it said that sharp things like claws, fangs and spinal tips wouldn't work well for intense electrostatic fields). Then he talked about the skin being made of an insulator to prevent the dragon from suffering damage from the electrical discharge and a part of the insulator being conductive. However, I changed the creature from scaly to feathered, so I ask, how would this apply to a bird?
The bird cannot depend on magic or technology. I intend to make the bird recharge by flying through the charged clouds, if necessary being the target of electrical discharges until it has enough energy to launch a lightning bolt. The thunderbird is not a wild species, so it lives with humans as a mount for them, just as horses do. No need to worry about the rider, I already have in mind a way for the rider not to get hurt while riding the bird. Suggestions for changes to the bird's physiology and the environment in which it lives are welcome. If the bird's dimensions are relevant, I've found an image that pretty much represents the size I plan it to be: