User blog comment:The Reptile King/Reptile Kingdom Wildlife/@comment-28144855-20160818001904/@comment-27950421-20160818123204

They are all roughly the same size. Dragon Halks do have a tendency to be a bit heavier though, they have denser bone and muscle to better suit being a war beast.

As for training, well it really depends on the individual. Dragon Halks tend to be a bit aggressive, sometimes they get a bit snappy when irritated. Thunder Halks are usually a bit hyper active so they don't always pay attention. Ice Halks tend to be a bit more sedentary so they can be a bit lazy sometimes. It's less of them being hard to train and more of the trainer needing to know how to work with or around their individual quirks.