A dimensional question for a sticky situation.

[TheStratovarian]

Okay, I have to briefly setup the scene, to help with the question.

We have a gargantuan old blue holding the mage (me) hostage in a cave. The party is level 7. The dragon is evil, and the dragons eggs are within reach of the mage through hero points to escape.

Worst case, is the party mage pulling an us for them deal.

But I need to make sure its legal in design. I wanted to cast the spell Mirror Hideaway. https://www.d20pfsrd.com/magic/all-spells/m/mirror-hideaway

And hold the eggs hostage in the extradimensional space. Since I have the means to send the mirror elsewhere that would destroy the eggs.

I wanted to ask if dropping the mirror hideaway into a bag of holding would eject the dragon and eggs into the bag? The spell would enter stasis, or if i could destroy the bag as the mirror entered and trap them?

The particular wording is why im wondering. "If placed inside such a space, they cease to function until removed from the extradimensional space. For example, if a bag of holding is brought into a rope trick, the contents of the bag of holding become inaccessible until the bag of holding is taken outside the rope trick."

The spell ceases to function, which would mean that it goes out is what im guessing, but wanted to ask here. Even if the spell goes, the dragon leaving the mirror would rupture it, killing the dragon in the bag of holding.

[Claxon]

I'm having trouble following your question, but I think the answer is no. This wont trap them the way you want.

[TheStratovarian]

Ah, sorry, let me try to phrase it better.

If the dragon enters the mirror spell through a smaller form first.
I toss the mirror into the Bag of Holding.

Is the dragon effectively dead at this point due to the rules on interactions of those type of effects?

Either when the spell is nullified from dimensional effect rules or I dismiss the spell and its shunted into the bag, which rips from weight inside and everything lost to the void?

I hope thats a bit clearer.

[VoodistMonk]

I believe that you're correct, actually. If you trap the dragon under one effect that will end upon being placed in the bag of holding, and the dragon will break the bag upon being released from the effects that originally trapped it... Yes, it now follows the rules associated with the bag of holding and the contents of the bag are lost to the void.

[Zarius]

The mirror becomes, for the duration of the spell, an extradimensional space. We have rules, which you've quoted, that describe the interaction of one extra/non-dimensional space entering another.

The extradimensional space, itself, would not cease to exist, merely the gateway into it (the mirror). The timer on it, just as if it entered an AMF, would continue to count down. The question here isn't really "what would happen to the dragon", because you, yourself, already quoted the rule. The REAL question is "what happens to the dragon if it's still in the mirror when the the timer runs out." THEN it would be expelled into the Astral plane, because that's where the pocket itself - with no other egress - collapses to.

[Claxon]

So my thoughts, because I don't know what your plan is but as I understand it:

1) You want to pull the dragons eggs into a mirror using the Mirror Hideaway spell?
This maybe works, maybe doesn't. It's unclear if the spell only allows creatures to enter, if it does the eggs aren't creatures (yet).

2) You want to then trick or convince the dragon into entering the mirror, which would require the mirror to be the size of the dragon or for the dragon to reduce in size?
This probably doesn't work as the dragon could instead just dispel your spell and the eggs would reappear.

3) Assuming the dragon does willingly enter the mirror you're questioning what happens if you place the mirror in another extra dimensional space, correct?

The mirror dimensional space couldn't be accessed, but nothing happens to those inside the dimension. Even destroying the mirror wouldn't do anything to those inside, extra-dimensional planes aren't well explained, but typically their contents are stored in an effectively empty part of the astral plane.

You also can't dismiss the spell once you put the mirror into the bag, as you no longer have line of effect to it.

Does this answer your question?

Or can you make a bulleted list of your plan so I can more clearly understand what you're attempting to do.

You might be able to strand the dragon in the astral plane, but that's probably the best you could do.

[Zarius]

Or, alternatively, throw someone down it's throat who can go in to what I refer to as Full On Blender Mode (TM). Natural attacks galore! Turn it into paste from the in side out! (I have a Kitsune Kyubi with claws and Deadly Grace just for this kind of situation.)