Waking Nightmare

[The Total Package]

Looking for any ways to extend the duration of Waking Nightmare.

You fill the creature's mind with a terrifying vision. The target must attempt a Will save. A creature frightened by this spell takes 1 additional mental damage each time it's hit by a Strike.

Critical Success The target is unaffected.
Success The target is frightened 1.
Failure The target is frightened 2. If it's asleep, it wakes up and is paralyzed for 1 round.
Critical Failure As failure, but frightened 3.

[Squark]

A Hobgoblin's Merciless Lash feat will prevent the frightened condition from ticking down to 0. The dragon style monk has a similar feat.

[Eoran]

Resentment Witch familiar ability would extend the paralyzed duration. Possibly also the Frightened condition, though that depends on GM ruling.

But that cannot be gained from the archetype.