Language discrepancy between SRD and PHB

Question

In the Systems Reference Document (SRD) text of polymorph it is stated that

The spell has no effect on a shapechanger or a creature with 0 hitpoints

However in my PHB copy it is worded as

An unwilling creature must make a Wisdom saving throw to avoid the effect. A shapechanger automatically succeeds on this saving throw.

Implying that a willing shapechanger can be effected since it only allows a success on a save that is only rolled by an unwilling target. I was unable to find an errata on this subject.

What is the RAW in this case? The SRD was published later than PHB--does it make it more official? Is this even an intentional change? Is there an errata I am missing somewhere?

Answer 1

The spell wording in your PHB is out of date

The SRD, D&D Beyond, and the revised PHB agree that your version is not the most up-to-date version.

If you look on D&D Beyond, you can currently find the most up-to-date information. The description of polymorph on DDB tells us:

The spell has no effect on a shapechanger or a creature with 0 hit points.

My PHB says "first printing August 2014 (This printing includes corrections to the first printing.)” and it includes the exact same phrasing as I quoted above (the same as on the SRD and DDB).

Oddly enough, I cannot find an errata that changes the wording of the shapechanger part in the PHB. The errata does note when the "0 hit points" part was added however.

SRD is not an official rules source

Note that the SRD is not an official rules source. It just so happens that it was updated after your PHB was printed and thus happens to be right in this case.

Answer 2

While the SRD does not override the PHB, the newer printing of the PHB has the same wording as the SRD, as covered by Rubiksmoose.

According to the Sage Advice Compendium:

The fifth edition of D&D has three official rulebooks, each of which was first published in 2014:

• Player’s Handbook (abbreviated PH)
• Monster Manual (abbreviated MM)
• Dungeon Master’s Guide (abbreviated DMG)

The SRD is not even mentioned here. On its page, it says:

The Systems Reference Document (SRD) contains guidelines for publishing content under the Open-Gaming License (OGL).

So no, the SRD is not an official rules source and does not override the official rulebooks. It exists as a tool for publishers, not as a free rules resource. That role is occupied by the Basic Rules.