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.
When hovering over an ability, the tooltip will tell you whether or not that attack is weak or strong against certain pet types. Additionally, you can hover over the opposing team's pets and view their attacks during combat. This will be important since it’s a good idea to pit a pet that's strong against the opponent's pet who's vulnerable to that type.
Some players have been surprised by these apparent flaws—even players who have been eagerly awaiting WoW Classic's release based on fond memories of vanilla WoW. In truth, it has been so long since WoW first released, players' memories may not always be accurate. Some details might be fresh, but others might be lost in time, and it's those lost details that could surprise players revisiting the original experience in WoW Classic.
To fill our pool of beta and stress test participants, we’ll be choosing dedicated players who meet select criteria from both the WoW Classic beta opt-in and the standard Warcraft beta opt-in. Participants will also need to have an active subscription or active game time on their Battle.net Account. While opting-in to the beta is the primary way to make sure you’re in the running to join the test it doesn’t guarantee an invitation to the closed beta test. We may also consider additional factors such as how long a player has been subscribed to the game so that we have the right mix of players to ensure great feedback toward making WoW Classic the very best experience for the community.
Four groups of Zygons attempted to make Earth more like Zygor: those who arrived in the 12th century (TV: Terror of the Zygons), those that arrived in the 16th century and plotted to invade in the 21st century (TV: The Day of the Doctor), those that arrived in 1909 (PROSE: Sting of the Zygons), and those that arrived in the late-20th century. (HOMEVID: Zygon: When Being You Just Isn't Enough)
The original World of Warcraft was released in 2004, and World of Warcraft Classic aims to recreate the state of the MMORPG before its first expansion, The Burning Crusade, was rolled out in January 2007. Previously, players looking for a “vanilla” version of the game were only able to experience it on custom servers such as Nostalrius, which Blizzard shut down in 2016 to protect its intellectual property.