So as a few here may remember I was at one time having some issues with Enzo acting aggressively which I discussed in this thread here Having some aggression issues with Enzo - Mastiff Forum Well a couple months have passed and very fortunately I have some very good news to report ! It seems that Enzo has done a complete 180 and is now acting quite submissive, far more then I could have ever expected... Just seems like something clicked and all of a sudden he's back to goofy happy puppy again....Even in his play with other dogs he's acting quite submissive..At the dog park he can get overwhelming to smaller dogs and from time to time the older dogs have to discipline him and he immediately goes submissive.... its quite funny to see this 160 lbs bear of a dog getting Alpha rolled by a 35 lb Sheltie LOL ... ENzo has absolutely zero interest in fighting with any dogs of any size...he is possibly the least Alpha dog in the dog park, just this big happy slobbery marshmallow ! So my guess is that Enzo was going thru hormone spikes as he developed and it was causing some teenager like emotional issues...I was reading that during development a dog can have as much as 10X elevated testosterone levels as to what he will have as a full adult.. And I have to say that very recently we have seen a fairly dramatic increase in Enzo's muscle mass density that would time out perfectly with the behavior issues we seen .... We have even had guests back at the house and Enzo has behaved just like he used to...happy and friendly and totally calm... One thing we have done is taken Enzo many times to the dog park where he has the ability to openly socialize with other dogs and people, we have pretty much taken him every second day weather permitting .. This has worked wonders for him and he's now so much happier and friendlier, i believe that taking him to the park was the best thing we have done with him..it seems it has given him something to live for and now he's behaving better then I ever could have expected..its amazing , it truly is...Enzo went from being the most insubordinate puppy you could ever imagine to becoming possibly the best behaved adolescent I have ever seen..As long as we go the dog park ever odd day he's an angel and seems to actually try to please us... seems he has forgotten all about being a big tough angry dog and taken more towards the socialite marshmallow that can mooch free food ....... Enzo is very smart and willful and its apparent that he's highly social and loves being around other dogs..my previous dogs thing was chasing my RC car, and once we had that figured out he was a dream to live with...it seems Enzo's the same way his thing is the dog park... Myself I am happy Enzo's taken towards being more submissive, people at the park get a laugh at the poor guy sometimes but its much better then having him go the other way ....