They might not be a meaningfully supported archetype in most sets, but you still find them, often as a boon for doing something simple like triggering heroic on Phalanx Leader, to juicing up a card like Ancient Animus, or just to make an aggressive deck more viable
Opening Ceremony This six-mana costing sorcery makes six mana so it fits into Storm brews
I hear your protestations now
Both of them do a good job of showing up the expansions new mechanics and key features, and after playing them I dont think a third one would have been necessary, especially because it would have just been another Ruby/Emerald like last time
Simply talk to Jonathas, the same NPC that will sell the Behemoth mount, and you will automatically get the Certificates
In aggro and midrange, its still useful