Does the Sword of the Planes have a +4 bonus against literally any outsider?

Question

In our Pathfinder game, we recently came upon a Sword of the Planes.

This longsword has an enhancement bonus of +1 on the Material Plane, but on any elemental planes its enhancement bonus increases to +2. The +2 enhancement bonus also applies whenever the weapon is used against creatures native to the elemental planes. It operates as a +3 longsword on the Astral Plane and the Ethereal Plane, or when used against opponents native to either of those planes. On any other plane, or against any outsider, it functions as a +4 longsword.

We initially interpreted this weapon (when used on the Material plane) as being a +1 weapon normally, +2 against elementals, +3 against creatures from the Astral or Ethereal Planes, and +4 against other outsiders. We weren't sure about what it would do to native outsiders, so we deferred that decision.

However, a second reading of the rules says that it is +4 against any outsider, not any other outsider. This seems odd, since there are only a few creatures native to the elemental, Astral or Ethereal planes who aren't outsiders.\$^1\$

What is the correct reading of the rules? Does the Sword of the Planes have a +4 bonus against literally any outsider, or just any outsider not covered by the rest of the description? And is one interpretation more balanced than the other?

---

1: Searching for non-outsiders, I have found Astral Dragons, Devourers and Ouroboros in the Astral Plane, Cloud Dragons in the Plane of Air, Crystal Dragons in the Plane of Earth, Magma Dragons and Fire Whales in the Plane of Fire, Brine Dragons, maybe some Merfolk, maybe some Sahuagin, possibly some Scyllas (by random encounter table) and possibly some Krakens (by random encounter table) in the Plane of Water, and Phase Spiders, Thought Eaters, maybe Ectoplasmic Creatures, Nightmare Dragons, Etheric Dragons and Dream Dragons in the Ethereal Plane. Admittedly, this list is less small than I first thought, although the majority of the occupants of a foreign Plane are still outsiders.

Answer 1

TL;DR: No official ruling, but I think you should take the highest applicable bonus. e.g.: +4 vs. all outsiders

I've looked around for a while and found that similar questions had come up as early as 5 years ago. In the linked thread, respondents pointed out that there was no clause exempting the native subtype from the weapon's effects. No clarification has been issued by Paizo regarding this matter or how the blade affects outsiders that inhabit the elemental/astral/ethereal planes when encountered on the material. It is unlikely that any clarification will ever come considering that the item itself is pulled almost word-for-word from D&D 3.5 and even earlier versions of the weapon exist in prior editions.

I'm inclined to believe that the original intent of the weapon is for it to have the +4 bonus against all outsiders. This is because mentions of the sword appear in Pathfinder and 3.0 content. Often, this is done while specifically calling attention to the potent threat the weapon is to various outsiders.

• Skulls and Shackles spoiler item is a Pathfinder example.
• Paragraph 5 from Dragon magazine issue 293 likewise mentions the sword's threat to outsiders in the 3.0 Forgotten Realms setting while discussing the genasi. The genasi are all native outsiders and have elemental themes (though they lack elemental subtypes).

That being said, I've seen this in two campaigns run as RAW, (with the +4 vs. all outsiders). By and large, I found it to be balanced even in a campaign that had very high numbers of outsider enemies. The sword does not bypass alignment-based DR of outsiders since it does not reach a +5 enhancement bonus, so DR #/Good is still a formidable defense. The Sword of the Planes is priced at 22,315 gp. This puts it between the costs of a +3 and +4 weapon. In return, you have a +1 sword most of the time, except when travelling abroad at a planar scale or when being harassed by foreign planar entities.

Even comparing it to weapons with the Bane weapon property, cost-wise it is not doing anything stupendously more powerful. Bane gives an additional +2 to hit (above the base weapon) and then +2d6+2 (including new bonus) to damage against a single outsider subtype. In comparison, the Sword is giving a +3 to hit vs. all outsiders (above base weapon), but only +3 damage to all outsiders at 14,000 gp more cost (compared to a +1 bane longsword). This price seems relatively fair for what you get.

As always, your GM has the final say on how the Sword works, but I think that the Sword is a balanced item and that permitting it should not cause much, if any, trouble in your game.