Archivist's Seal - 2e to 5.5 Conversion

This palm-sized brass seal bears the image of an open book surrounded by tiny, shifting script. When pressed into warm sealing wax, it leaves an intricate arcane impression that records the condition of a document and its contents at the moment it is sealed. No two Archivist's Seals create exactly the same magical impression. 

Arcane Seal. As a Magic action, you can use the seal with a small amount of sealing wax to seal a letter, scroll, book, packet of documents, or similar written work. The magic records the physical condition and written contents of the material when sealed. The seal remains active until intentionally broken.

Tamper Evidence. If the material is opened, damaged, has pages added or removed, or has writing erased, replaced, or altered, the seal records the tampering. Obvious tampering requires no ability check to recognize: the open-book symbol closes and the surrounding script becomes jagged.

Examining the Seal. A creature can spend 1 minute examining an intact or broken seal and make an Intelligence (Investigation) check.
DC 10: determine whether the seal was legitimately broken or physically tampered with.
DC 15: determine whether the contents were altered after sealing and identify the general nature of the alteration, such as added writing, removed pages, substituted pages, or erased text.
DC 20: reconstruct the sequence of tampering well enough to determine whether the seal was broken before or after the contents were altered and identify sophisticated attempts to conceal the alteration.

Arcane Examination. A creature proficient in Arcana can instead make an Intelligence (Arcana) check.
DC 15: recognize the seal as magical and determine whether its enchantment is still functioning.
DC 20: recognize magical interference, suppression, or an attempted magical forgery.
DC 25: identify the magical signature of another Archivist's Seal or similar magic used in an attempt to counterfeit the original impression.

Authenticity. Each Archivist's Seal leaves a unique magical signature. A creature that has previously examined a genuine impression from the same seal has Advantage on checks made to authenticate another impression from it. Mundane copies don't reproduce the magical signature.

Counterfeiting. A creature proficient with a Forgery Kit can attempt to reproduce the physical appearance of an impression, using the normal rules for an ability check with that tool. A result of 20 or higher can fool a casual visual inspection, but doesn't reproduce the magical signature and can still be exposed through magical examination.

Limitations. The seal records changes, not truth. It can't determine whether a statement was truthful, whether a signature was genuine when originally sealed, or whether the document is legally valid. Breaking the seal normally ends its ability to record further alterations, but the broken seal retains its record of prior tampering for 30 days.