[Hearthstone Science] League of Scientists #01: Djinni of Zephyrs

Welcome to the League of Scientists series, where we explore cards added in League of Explorers. First up, we have Djinni of Zephyrs, a card with nearly unlimited potential for shenanigans. But how does it work?

Question 1: When does Djinni trigger?

When this card came out, I naturally assumed that it would trigger with the same timing as Violet Teacher, because they have identically worded card text. Was I on the mark? Let's find out.

First, let's outline the Phases of casting a spell. After paying for the spell and assigning a target, you proceed to the On Play Phase, where Violet Teacher, Questing Adventurer and Counterspell trigger, then the Targeting Phase, where Dragonkin Sorcerer, Eydis Darkbane and Spellbender trigger, the Spell Text Phase, where the spell and all its effects resolve, and finally the After Spell Phase, where Flamewaker and Wild Pyromancer trigger. Also note that between Phases, we process deaths until no new deaths are found.

So, where does Djinni trigger? Djinni is a trigger in the After Spell Phase, meaning that it triggers alongside your Flamewakers and Wild Pyromancers. In addition, it has a low priority, so it always triggers AFTER them in this Phase, rather than in order of play.

Watch what happens in this video. We play a Flamewaker after Djinni of Zephyrs, yet Djinni triggers after it. We also see that death processing is suspended until all After Spell Phase triggers resolve.

This lets us predict the following - If after death processing from the spell completes, you control an in-play Djinni AND the minion you targeted with the spell is currently friendly, the Djinni will trigger.

For example, if you cast a spell on a friendly minion, but Spellbender intercepts it, Djinni of Zephyrs will not trigger.

Another example, if you cast Shadow Madness on an enemy minion, it becomes a friendly minion, and your Djinni of Zephyrs will trigger.

We'll come back to Shadow Madness later.

Another rule is that the friendly minion target does not have to be alive, because you still control it in the Graveyard. This means that Djinni can combo with spells like Naturalize, although they too will die.

Question 2: What kinds of spells work on Djinni?

The answer is - every minion-targetable spell in the game. But how can this be the case? Let's look at how spells use conditions in Hearthstone.

First, there are targeting conditions. These are checked only when you pay for and target the spell. They are not checked a second time when the spell resolves.

This means that even if the spell's target changes its stats, the spell is redirected or the spell is copied, it will not check its targeting condition a second time, it will just resolve. MtG pros, forget you ever heard the term 'fizzle'.

Let's look at some examples. First, Demonfuse requires a Demon target - this is a targeting condition.

Second, Shadow Word: Death requires a 5 Attack or higher target - this is a targeting condition also.

Note that spells that require an 'enemy minion' are also targeting conditions. This means that you can copy enemy-only spells like Execute if you steal the minion before the After Spell Phase, such as by killing a friendly Sylvanas Windrunner using Violet Teacher shenanigans.

The other kind of condition is a conditional effect. These don't restrict how you cast the spell - they are only checked when the spell is resolved. That means that each copy of the spell checks the condition independently.

For example, if you cast Demonfire on a friendly Demon, your Djinni takes 2 damage because the condition is rechecked.

Second, if you cast Ice Lance, Djinni take 4 damage or become Frozen based on their personal condition.

Finally, if you cast Light of the Naaru, Lightwardens are summoned or not summoned based on each Djinni's post-heal state.

Question 3: How do Mind Control and Djinni interact?

As previously discussed, Djinni triggers in the After Spell Phase. Since the target minion is now friendly, Djinni will copy spells like Mind Control and Shadow Madness. But what happens as a result?

As we just saw, they gain summoning sickness, as though newly taken control of. This is because they try to move from their current controller to you again. This has a second side-effect - if your board is full with 7 minions, they will instead die and go to the Graveyard zone, since they think there is no room. In addition, if the spell was Shadow Madness, they will again attempt to move to your control in the End of Turn Phase, which will again check the 7 minion limit.

This mechanic can be seen with other cards - For example, if you have Baron Rivendare and Anub'arak in play, Anub'arak will try to add himself to your hand while already in it. If your hand is full, he will discard himself.

4. While testing, we found a bug. As it turns out, Keeper of the Grove will trigger Djinni of Zephyrs. See for yourself.

Further investigation showed that Djinni was triggering in the After Play Phase. This Phase used to be called the Secret Activation Phase, but Rumbling Elemental triggers in it now, so it has been appropriately renamed.

5. Here's some clips I had left over. If you want to learn more, I'll leave links to the Advanced rulebook and the Djinni of Zephyrs wiki page in the description. Thanks for watching, and enjoy making your own Djinni of Zephyrs interaction videos!