Inven Global’s third and last card reveal is a new Epic Priest minion: Mana Geode. It sits at a somewhat standard 2/3 for (2) statline, with the effect: "Whenever this minion is healed, summon a 2/2 Crystal". Although there are other ways to trigger the text, it will essentially be a pseudo-Inspire card.
The Inspire mechanic was introduced to Hearthstone with The Grand Tournament, but has since failed to cement itself as a particularly popular or interesting mechanic. Some Inspire cards such as Savage Combatant and Nexus-Champion Saraad did have their moments in the sun, but apart from Thunder Bluff Valiant, none became mainstays.
Mana Geode reminds me most of Kodorider and Murloc Knight - potentially gamebreaking long term value nestled within a mediocre body - although it does trigger slightly differently.
Mana Geode’s low mana cost and not-too-terrible stateline ensures players can easily throw it on the board on Turn 2, pressuring their opponent to remove it as soon as possible. So far so good. The problem lies, however, in that other powerful 2-drop minions can easily match its pressure. Totem Golem and Alexstrasza's Champion both are unfavorable matchups for Mana Geode.
It also should be criticized that Mana Geode’s conditional effect is, well, too conditional. Had it been worded as "Whenever a character(or even a friendly character) is healed", the card would have felt much stronger.
Mana Geode does offer some synergy with the new expansion’s powerful additions to Priest, but Pint-Size Potion will probably be much more effective when played with Shadow Word: Horror, Wild Pyromancer or Shadow Madness. Similarly, Kabal Talonpriest should reap more value when used alongside Wyrmrest Agent.
Unless a whole new Priest archetype emerges, Mana Geode's chances to make it into the meta as of now are slim, although it may still find a home in Dragon Priest or elsewhere after another wave of cards leaves Standard. On the bright side, at least the card will improve Priest’s Arena draws (by a hairsbreadth) by reducing the probability of getting three dud Epics!
Mean Streets of Gadgetzan still has a few more cards to offer, and we should hold judgment until everything is released - remember Kabal Crystal Runner? Perhaps the next reveal will unlock a combination powerful enough to let Mana Geode shine. The coming days will tell.