This tutorial will ensure that the beginning of your journey will be a smooth one. It provides information that will help you find your way when you get lost, as well as tips that will offer guidance and advice as you march on towards greatness. It is not an exhaustive guide, however; it neither can nor wants to unveil every secret of Azeroth to you. That glorious task is left up to you as you explore the world yourself. Think of this guide as a touchstone for your early adventures: enough to get started, but too little to spoil any of the awesome surprises that await you in Azeroth.
Zygor was the home planet of the Zygons. (PROSE: The Bodysnatchers) It was known to be warmer than Earth and covered in water, which was in the form of lakes with a different mineral composition than those of Earth. There were also no icecaps on the planet. Native lifeforms of Zygor included the unaltered Skarasen and the Zygons. (TV: Terror of the Zygons)
Only really to expand on Gráinne's comment as regards the 'collecting' and 'roster development' sections - which are, as said 'distinct' although they are intrinsically linked - I would like to point you in the direction of the in-game Achievements > Battle Pets > Collect tab. There are a series of achievements called Raiding With Leashes, pretty much all of which can be completed via the auction house - if you have the gold/inclination - or by completing old raids.