Price of invincibility

[My Self]

As a class feature, what would the equivalent cost for 1 round of bona fide 100% invincibility*? Would it be a capstone power? 9th level spell? Would it require some other opportunity cost? What about more than 1 round?

*invincibility defined more or less as follows::

Automatically succeeds at all saves, defensive stat checks, and defensive skill checks (unless you choose to fail)
If an effect would affect you on a successful save, it instead does nothing
Effectively unbeatable AC, CMD, and SR
Cannot take any damage or drain of any type
Cannot be forced to take penalties because of enemy action/presence (such as through a Mesmerists's stare, or through the Antagonize feat)
Cannot unwillingly have active effects dispelled
Cannot unwillingly be moved or impeded by enemies (such as through magically creating difficult terrain or through Weapon Mastery difficult terrain)
Cannot drown, suffocate, or die of other unusual conditions
Immunity to all status effects, including death
Immunity to magic, including Wish and Miracle

Ideally, cannot be negatively affected by enemy presence or action, or by natural hazards

[Dox of the ParaDox twins]

Definitely a capstone, maybe it could be a spell if it had an insane cost, maybe even an xp cost like 3.5 had

[Cyrad]

Even wish can't do all of that.

[Zironic]

Assuming you put some reasonable limitations on the power, such as the inability to perform offensive actions. Wouldn't it be functionally equivalent to timestop?

[Plausible Pseudonym]

There's a 3.5/3rd party psionic power (Timeless Body) that does that for one round, it's 9th level.

There's also an Alchemist/Psychic spell that puts you in an invulnerable suspension for rounds or minutes per level, but you can't act during that time and it can be dispelled.