On the top of their hierarchy, what do they require or look for in a leader?
The requirements for a Zver alpha are set at a very high standard. Depending on the current alpha and the laws of the pack, those who seek after the position may have to kill the current alpha along with his mate and her cubs. In the more laid back packs, a potential alpha only has to prove himself by chasing out the current alpha and any of his male cubs.
How is their hierarchy set up?
The hierarchy of the Zvers works very much like a pride of lions. The largest and strongest male is the alpha so-to-speak and all other males are ranked above the females.
What do they call their leaders?
Like wolves, the leader would be called the alpha. The title of alpha, however, can only be held by a male in a Zver pack/pride. The alpha's mate is considered only slightly above the rest of the pack. She does not have an official title really, though in Zver language the other Zvers would probably call her 'm'lady' to be more formal when speaking to her.
In the case of the alpha, he is to be addressed as 'my alpha', or 'm'lord'.
Are there such things as princes and princesses?
There are not exactly princes and princesses in the Zver packs. Because most females are ranked below even the lowest males, female cubs born to the alpha and his mate are treated much like any other female cub. They recive no special treatment.
The same goes for the male cubs. The alpha's male cubs, however, are given first share of the meat that is brought back for the cubs in order to help them grow to be stronger than the others so that they can, one day, lead their own pack/pride.
Even if the alpha and the female has cubs, their female cubs are the lowest no matter their royal blood?
Well, their female cubs aren't the lowest, but they're at the same rank as all other females in the pack besides the alpha's mate.
What do normal members of the pack/pride call the alpha's male cubs?
The alpha's male cubs are usually referred to as amirs(amir singular) by other members of the pack.
How does royal blood play into the Zver hierarchy/Does it help determine the alpha?
The leaders aren't so much considered 'royalty'. The alpha is always the strongest male in the pack, which is why his male cubs are treated specially in order to be sure they'll be strong enough to carry on the family genes. Which means that if a rougue came and took over a pack, killed all the male cubs as well as the old alpha and his mate, then had cubs of his own, they would be treated in the same way as the past alpha's male cubs and would be prepared to go out and take or create a pack of their own.
An alpha can come from any line, though some Zver lines, like wolves or dogs, are more pure in blood and so may carry traits that could be considered 'royal'. They may be stronger and healthier than other Zvers, perhaps they carry themselves with more pride and confidence than others. It just depends on their line.
But, as stated, there isn't exactly royalty. As long as the alpha can hold control over his pack, his sons will be amirs.
What about like the fighters? What would you call those zvers who fight to protect the amirs and etc.? Or is it just none?
The entire pack works as one to protect the alpha, his mate, and all of the cubs in the pack(amirs, regular males, and all females).
When something threatens the safety of the amirs themselves, the older males and several of the females will band together to fight off the attackers. However, the moment the alpha is defeated, all of the pack members will back down and the amirs will be killed without resistance from the pack itself(though the amirs will do their best to fight, and some do manage to escape unharmed, though not often).
So, all in all, there aren't any specific pack members assigned to protect the amirs in an attack. If the alpha is killed or driven off, the amirs will be left unprotected to fend for themselves.
How large or small are average prides/packs?
The average amount of Zvers in a group would be 6-8. The largest known group is 12.
You mentioned they are similar to both wolves and big cats, are there any other animals they're similar to/which characteristics?
Zvers are similar to wolves and cougars mostly, though, as stated in my answer above, their hierarchy is closest to that of African lions.
What characteristics do they share with wolves?
They mostly communicate through barks and howls. They have a strong sense of smell and move with the more bouncy gait of a wolf rather than the smooth fluid motion of a feline. However, they can climb trees and some tend to scream like cougars when extremely angry or when fighting.
Can Zvers feel protective or enjoy the company of humans other than their own?
This really depends on the Zver in question. They are extremely loyal to the human they bond to and would do nothing to harm the human in question unless they had no other choice. However, in some cases they will protect friends of their companion, though most don't particularly enjoy the company of the other people.
What are their learning capabilities? Are they similar to canines in their ability to learn things, such as certain jobs? (ie. security, drug search, search & rescue, etc.?)
Yes, they are like canines in this sense. They can be taught and trained just like most canines. This ability varies depending on each Zver as well. Some are actually willing to learn, while others can be extremely stubborn and refuse to take the time to listen. And of course, a Zver can only be trained by its companion. He/she won't usually listen to anyone else.
How do they feel about other animals? Are they just food to them, or can they be friends/companions/etc.?
Zvers are very indifferent to most species. Due to the fact that they have been trapped in the lab, they don't know much, if anything, about the wildlife on Earth. They do seem to recognize rabbits and deer as food(perhaps there are species close to them on their planet?) but when it comes to creatures such as wolves, dogs, big cats, etc it would depend on the personality of a Zver. The more vicious zvers were probably rogues or strays on their original planet and don't seem to care for the company of the seemingly 'weaker' species on Earth. However, some of the gentler Zvers may enjoy the company of species close to theirs.
Did zvers know anything about technology? Did they use locks and keys?
Zvers themselves do not know about technology. They are pretty much just animals. Much more intelligent than the animals here, but they're still animals. Zvers go by instinct and pack laws(which are usually created by the current alpha, so they can change drastically with each new alpha).
So no, they didn't use locks and keys. The aliens who share their planet are highly advanced though, and have a great deal of technology.