i play with a monk and a warrior, so i use a fox (probably switching it to goat or sporebat if the 10second nerf is true) without a warrior i would always use a plainstrider (instant 3 stack sunder armor during burst) spirit beast for mastery, devilsaur for crit buff and ms debuff or quilen but sometimes we split and i enjoy having ms up on both. rhino if i need the 4% physical it literally all comes down to what class you're playing with so let me know the comp and i'll give you the stable roster.
with the nerf to fox duration spore bat is looking like the way to go 5% haste for healer and undispellable.. just a crappier range
Retard sickness : when you're playing 3v3 Arena and spam icelance like a retard the whole game, you contract Retard Sickness. After thirty seconds you get kicked from the game unless you stop playing like a retard.
A solo queue that puts you into controlled situations (not even against players most of the time, just NPCs) where you need to practice a certain aspect of your class, or react to an important ability of another class. You get graded on your performance and can repeat the arena as many times as you want to improve/get a better score.
As you progress the situations get more and more complex and involve more people/abilities at once. Eventually you graduate to the real Arena.