Spike Stones - save per square or per move?

[FelixA]

The rules read,

Spike stones impede progress through an area and deal damage. Any creature moving on foot into or through the spell’s area moves at half speed. In addition, each creature moving through the area takes 1d8 points of piercing damage for each 5 feet of movement through the spiked area.

Any creature that takes damage from this spell must also succeed on a Reflex save to avoid injuries to its feet and legs.

I'm seeing some folks state that the Reflex save is made one for the move through the area, while others state the save is for every 5 foot square. Is there any definitive ruling on this?

[Baarogue]

You're quoting the PF1 version of the spell. Is that the version you mean to ask about? This is the PF2 rules discussion board

If you mean to ask about the PF1 version, the save is made each time the creature takes the damage. The creature takes damage (no save) >for each 5 feet of movement through the spiked area.

The "injuries" are a movement penalty

PF1 Spike Stones wrote:

A failed save causes the creature's speed to be reduced to half normal for 24 hours or until the injured creature receives a cure spell (which also restores lost hit points). Another character can remove the penalty by taking 10 minutes to dress the injuries and succeeding on a Heal check against the spell's save DC.

[FelixA]

Crap! Somehow got on the wrong forum. Yes, it's PF1e

[Yonman]

FelixA wrote:

The rules read,

Spike stones impede progress through an area and deal damage. Any creature moving on foot into or through the spell’s area moves at half speed. In addition, each creature moving through the area takes 1d8 points of piercing damage for each 5 feet of movement through the spiked area.

Any creature that takes damage from this spell must also succeed on a Reflex save to avoid injuries to its feet and legs.

I'm seeing some folks state that the Reflex save is made one for the move through the area, while others state the save is for every 5 foot square. Is there any definitive ruling on this?

I don't think there's an official ruling but the syntax would indicate that if you move 30' through an area you take 6d8 points of damage, not 1d8 damage each 5 feet. Therefore, you make one reflex save for one movement action.