Does Valakut do damage if Dryad of the Ilysian Grove is in play, but dies before the trigger resolves? Take 2 (I did not understand the explanation)

Question

Stumbled upon an old question regarding Valakut and Dryad of Ilysian Grove, Link is below: Does Valakut do damage if Dryad of the Ilysian Grove is in play, but dies before the trigger resolves?

I am not quite following the ruling (Not a judge, just a lowly L0). In this case the effect is checked as it is being placed on the stack and also as it resolves.

In ruling 613.5 it states - The application of continuous effects as described by the layer system is continually and automatically performed by the game. All resulting changes to an object’s characteristics are instantaneous.

I would have thought that because the plains stops being a mountain due to dryad being destroyed, Valakut's trigger would not resolve. I understand the ruling with the mountain leaving the battlefield etc, but not quite this. I also understand another thread where Dryad loses all abilities but because losing ability is applied at layer 6 and type changing ability is applied at layer 4, even though dryad loses all abilities the lands are still every type. Thread as below: Why does Dryad of the Ilysian Grove grant all basic land types even if it loses all abilities?

Do explain why if Dryad dies as lands enter, when Valakut trigger resolves the it still does damage?

Thank you

Answer 1

Yes, Valakut, the Molten Pinnacle will still do damage, but only if there are still 5 other mountains in play without Dryad of the Ilysian Grove's ability.

I'll lay out three examples:

1. Player has Valakut with 5 Mountains, 1 Forest and Dryad and plays a Forest. The land enters as all land types and Valakut triggers, putting the ability on stack. Someone destroys Dryad before the trigger resolves, the trigger sees 5 mountains still in play, and so it deals 3 damage.

2. Player has Valakut with 4 Mountains, 1 Forest and Dryad and plays a Mountain. The land enters and is naturally a mountain so Valakut triggers, putting the ability on stack. Someone destroys Dryad before the trigger resolves. When the trigger resolves, it sees 5 mountains, but only 4 of them are 'other' than the one that caused the trigger, so no damage is dealt.

3. Player has Valakut with 3 Mountains, 2 Forests and Dryad and plays a Mountain. The land enters and is naturally a mountain so Valakut triggers, putting the ability on stack. Someone destroys Dryad before the trigger resolves, so the trigger does not see 5 mountains in play when it resolves, so no damage is dealt.

The trigger conditions on a triggered ability are only ever evaluated when they happen, a land entered the battlefield and when it entered it was a mountain. The second condition is called an intervening if clause, it forms part of the trigger condition but also is checked on resolution. This is laid out in rule 603.4 of the comprehensive rules.

603.4 A triggered ability may read “When/Whenever/At [trigger event], if [condition], [effect].” When the trigger event occurs, the ability checks whether the stated condition is true. The ability triggers only if it is; otherwise it does nothing. If the ability triggers, it checks the stated condition again as it resolves. If the condition isn’t true at that time, the ability is removed from the stack and does nothing. Note that this mirrors the check for legal targets. This rule is referred to as the “intervening ‘if’ clause” rule. (The word “if” has only its normal English meaning anywhere else in the text of a card; this rule only applies to an “if” that immediately follows a trigger condition.)

Answer 2

Okay, as a only occasional Magic player, I think I see the confusion the questioner has that seems to be "obvious from the rules" to responders.

• Plains is played ("enters the battlefield"). Valakut sees a Mountain enter the battlefield (because of Dryad, the card is a "Plains Island Swamp Mountain Forest") and 5 other Mountains on the player's side of the battlefield and triggers. The trigger goes on the stack.
• Dryad is destroyed in response to the trigger.
• Trigger resolves, hits the "intervening if", and checks to see "if you control at least 5 other Mountains". Note that the intervening if, and therefore whether the triggered effect resolves, says nothing about the land that entered the battlefield triggering the effect (which, yes, is now only a Plains). It simply is no longer relevant.
• Certainly, as Andrew says here and others said in the other question, if some of the "other lands on the battlefield" are no longer Mountains, "you" may no longer "control at least 5 other Mountains" and the effect would not happen. But again, that says nothing about the land played - it is not relevant to the condition.

The way you're reading it would be if the card said: "Whenever a Mountain enters the battlefield under your control, if it is a Mountain, you may have ..."

Or, more formally, per 603.4 quoted by Andrew and in the previous question's answers, the trigger event is "When a Mountain enters the battlefield under your control", but the condition is "if you control at least 5 other Mountains". Only the condition is "check[ed] again as it resolves", not the trigger event.