Interesting Diamond Spellstone/Treant Interaction

I don't know if this is common knowledge or not, but I was playing a Midrange Treant Druid just now against a type of Resurrect Priest in Wild and experienced a very strange interaction between Treants that had been summoned and died on their side of the board and their spellstone.  They were using the Radiant Elemental and Veilweaver to generate a ton of value similar to a Lyra deck might try to do.  Anyway, they had also played a few thief Priest cards to generate things like Soul of the Forest, and I also played Poison Seeds at one point.

Later, when the opponent played a 3 minion rez Diamond Spellstone I was expecting Radiant, Veilweaver, and a Treant as those are the only three minions that had died on my opponent's side.  Instead he got a Veilweaver and 2x Treants!

I was like, "WTF?!"  My Opponent was also like "WTF?!" and went bottom right to end the match instantly.  But in the few moments I had prior to his concede I realized the two Treants have different watermarks!  One was a Classic set Treant and the other was Naxxramas set Treant!  So despite the same artwork and same name, the game counted them as different minions in regards to the spellstone's mechanic.

Again, is this specific interaction common knowledge?  Does it sound like a potential bug?  Not that I really care as it's just one additional way a Resurrection Priest's game plan can get screwed up, but I am generally interested to hear if others have had similar experiences, or just your thoughts on the interaction.

It's probably not common knowledge, but it is definitely not a bug either. The different watermark is enough information to say they are distinct cards. Indeed, any single attribute being different would be, since that must mean the game data stores them separately, even if they share other attributes.

You can consider each card as a bundle of information, which off the top of my head would be:

• Card type (minion, spell, weapon, hero)
• Mana cost
• Attack (minions and weapons. Probably just a null value for spells and heroes)
• Health/durability (again for minions and weapons. Possibly also used for the armour part of heroes)
• Card text (just for the purposes of displaying writing on the card)
• Some function to enact the card text
• Tribe
• Card name
• Artwork
• Set/watermark
• Class (dual- and tri-classes might be individual pre-set options here, but there's lots of ways they could go about this)

Since each card can only have 1 'value' for each attribute, any being different must mean you're looking at a different card.

It's most likely a special case of how Hearthstone handles "different cards" mechanics internally.

Some of them, like The Caverns Below and Flik Skyshiv differentiate cards based on their displayed name. The latter would kill all minions named "Treant" and that's the reason it used to destroy both the 0/2 tokens and the spell named "Mirror Image"

While others, namely all Highlander cards and most likely Lesser Diamond Spellstone as well, look at the card's internal IDs. These see Treants and Doppelgangster's tokens as separate cards and allow multiple to be resurrected.

Well that's just an unfortunate event as its likely the treant tokens were distinctive cards, since team5 seemed content to simply create more 2/2 treants with different artwork, though its obvious they are all just 2/2 tokens with a hidden treant tribe.

While I am aware that the treants with different artwork were distinct cards, I couldn't have guessed that even with the same artwork they can be entirely separate cards by virtue of their watermark. Simply amazing.

I hadn't thought about the Doppelgangster tokens being different... but I guess they would be if they have different IDs because of their different artwork.  But yeah, I'm guessing this also works with say Annoy-o-Tron and the Annoy-o-tron tokens off of Giggling Inventor. Or if as a Priest you Mind Control the Ragnaros token off of Jan'alai and also play your natural HoF version of Ragnaros, you could later technically resurrect two Rags off of a single Diamond Spellstone.

It's definitely a very strange interaction, but I don't really see it as something that is going to come up regularly, nor as something exploitable so I doubt it'd ever be changed.  The mechanics of this game intrigue and confuse me at times!  :)