I have dogs. A mix who is about 10 or 11 years old, a Pit bull who is about 5 something, two small dogs one being a Rat Terrier who is about 6,6 1/2,a Lhasa Apso who is somewhere around the same age as the rat Terrier, then and Final, a German Shepard who is only in her 2's,she is my dog, the one in question. She is not human aggressive, and to be honest has never been so much dog aggressive but that all changed about a month ago. She attacked our dog the Lhasa Apso,and from what we saw no apparent reason, once she got pulled off, the warden (The Pit Bull),came and attacked Gunner (It honestly was not too much of a surprise, his name fits what he does best).The Pit bull has to show the Lhasa apso up about every oh blue moon, anytime the Lhasa gets too outta hand, but the German shepherd, she has never done that, she was what really surprised us The most. I have literally searched around and only found a few things. She could hurting, could have been jealous at the time due to her not being the first one abled to greet my mother and sister (The dogs enjoy them because they readily ever see them),then 3 she could have "Magically" got triggered (that makes no sense to me, someone with Knowledge explain that?),then 4 ,Hierarchy, which I think is why she is doing this aggressive behavior. That is only 1 of the 3 fights she has gotten into. The second one isn't really a fight but could have been. This was an Encounter with the Terrier. He was doing his thing the warden our Pit, playing, and I don't know if our The German Shepered (she is girl BTW, and her name is Sugar),if she thought a fight was beginning or what, but she had the edacity to attack the Terrier!Which all she had time for was to snap and leap at him, before any real damage was done the warden jumped d\on her stopping everything. Yet NOBODY has any idea what is getting into her, someone have any clue, anyone else's dogs all of a sudden just begun attacking dogs. The third fight. Can't blame her, or anyone of the 3 large dogs for taking immediate action and nearly killing the neighbors dog who, well invaded our property. The warden actually knew this dog (she is a Female Pit).My guess is 2 females who are pretty "catty". We do know females and female shave absolutely no problem with fighting another female as with us humans, males generally wouldn't fight a female. Anyways,from what I see this was a complete territorial moment. This dog and her "Partner" have actually attacked my German shepered before, but then my Shepered was much younger, and less stronger, and more gutless. Well, today she proved herself a changed women. My 10 year old male dog,and my pit, and sugar very aggressively attacked her, of course now the dog came down I'm almost positive to try and punk Sugar out as they usually did, but this time, that back fired, extremely horribly. They would have killed her if we were not present. Sugar the German shepherd drug her by her back, ripped and bit at her private places, ripped her entire butt/back all to crap,noticed her biting her legs, aggressively just attacking her, while the 10 year old took bites,extremly harassed her, and the Pit Bull, our warden was indeed In for the kill, which it is pretty unusual for males to fight female.at this point the female Pit was in complete shock after realizing her partner was not gonna assist her and the numbers were against her. In shock I tried grabbing stick to break (wasted 40 seconds),my grandma was yelling ,and it was all just very bad, at this point my foot came in handy and I kicked sugar, which would only make her lift her head up and hover ,which I wasn't reaching my hand into the action and I generally stood a good 4 feet out of the fight, and on occasion I tried grabbing my dog, but I seriously wasn't gonna get bit. The poor Female Pit was throwing her head everyway snapping trying to ward the 3 dogs off, but my dogs were relentless. But eventually my grandma got ahold of the pit our warden, and surprisingly he actually got off the dog, Sugar on second thought was over with it, she was seeking revenge, but I was able to gain control over her.The Female pit trotted home with a very distraught body. My dog looked and felt like she just ate a bloody deer, while as Taz our Warden had some blood on him and actually had a bite wound quite close to his heart,and the 10 year old one didn't have too much (he wasn't too involved.)Honestly, this is revenge. I completely understand this fight, but seeing my dogs "inner Wolf" was actually Terrifying...... Have actually noticed my Dog is getting Revenge on any dog who ever showed such bad negativity towards her, those 3 dogs.... So if anyone has any ideas on why my dogs becoming such a Savage, please let me know so we can resolve the problem.