The 3rd-level spell Meld into Stone has a duration of 8 hours.
But what happens at the end of the 8 hours if the target does not (or can not) leave willingly?
Here are some relevant details:
- The spell is listed of having a Range of "Touch" but is not clear if you touch a subject on whom to cast the spell or the caster touches the stone to enter. Since the description always uses the pronoun of "you", not "The target", I will assume it is the caster.
- The spell doesn't require concentration. So in theory it is designed for a caster to use it for a long rest inside of a pillar for safety.
Per the spell description:
You can use your movement to leave the stone where you entered it, which ends the spell. You otherwise can't move.
[...] a change in its shape (to the extent that you no longer fit within it) expels you [...] The stone's complete destruction (or transmutation into a different substance) expels you...
As stated, a character could take a long rest and over sleep. Or a character is suffering from a previous entanglement and is rendered unconscious (not dead, not 0 hp, just unconscious), restrained ,or paralyzed.
There doesn't seem to be an ejection when the spell ends clause, nor a "you become part of the stone" statement.
If you cast meld into stone and are in the stone at the end of the spell duration, do you just stay trapped forever?