"Decrypted" is the term given to the upgraded uncroaked (or "popped again") Wanda creates after attuning to the Arkenpliers. Decrypt is used as a verb (he was decrypted), an adjective (a decrypted unit), and a noun (decrypted retain their stats), similar to the usage of uncroaked. Decrypted superficially appear to be alive, lacking the physical evidence of the trauma that croaked them.
Unlike uncroaked units, decrypted units do not decay.Erf-b1-p145
Decrypted are loyal to the tool wielder, regardless of past allegiances, but still remember their past loyalties, any information they knew in the past, and loves. Erf-b1.5-p033 They are also resistantErf-b2-p29 (but not entirely immuneErf-b2-p73) to Turnamancy, although the exact nature of their (in)ability to turn is unclear. They're not entirely immune to turning, though, as Ossomer demonstrated; this may be a factor of personal physical distance from the Arkenpliers.
Decrypted units have zero upkeep cost and retain more of their pre-death strength, if not full strength, than uncroaked.Erf-b1-p145
Units heal all their lost hits and are cleansed immediately upon decrypting. Their livery also changes to whatever their attuned master wishes, just like uncroaked.First Intermission 25 After a short bit of disorientation upon waking they are able to immediately start fighting.
Decrypted Natural Allies are units of the side of the wielder of the Arkenpliers, and don't count as a separate tribe, so if all members of a Natural Allies tribe are croaked, not even Decrypting them can allow to build more units of their former tribe.Erf-b1.5-p045
Though decrypted units will presumably tell Wanda anything relevant that has happened to them Erf-b1.5-p044, Wanda is capable of directly accessing the senses of certain units with natural thinkamancy (like Archons).
The unit is enslaved to Wanda and may suffer a major mental attitude adjustment (e.g. "You were correct, of course. Royalty is obsolete."Erf-b1-p145) possibly due to a change in its Natural Thinkamancy or a choice made by Wanda at the time of decryption; otherwise, the Unit retains all of its previous stats, abilities, and levels, but it may suffer a demotion if it was of a high rank and that position is already occupied by another Unit.
As with uncroaking, uniforms and insignia are changed when the uncroaked join their new side. Decrypted seem to gain Wanda's insignia Erf-b1-p144 rather than the insignia of their chief warlord Erf-b1-p116, but this is Wanda's choice for units she creates Erf-b1.5-p026 rather than a feature of decryption itself. Units like Wiener-Rammers with no uniform may suffer a change of color in skin or fur.Erf-b1-p146
Decrypted still are able to gain experience.
As they have zero upkeep, it is unlikely that any food pops for them, and thus unlikely that they need to eat and drink. It is still possible for them to do so however, as in the case of Gobwin Knob's dwagons consuming their foes.
It is unknown as of yet exactly how the Arkentools do what they do. It seems that they give Wanda an advanced form of Croakamancy, but it is a theory that it makes a combo-caster. Allowing Wanda to use a Croakamancy/Healomancy/Turnamancy spell to make the decrypted. Another possibility: could it be a form of Retconjuration, allowing Wanda to remake the croaked unit as she sees fit?
Being "popped again" is certainly a joking reference to the Christian concept of being born again, as being popped is the Erfworlders' version of being born, and Ansom, the one who coined the phrase, converted to Toolism upon being popped again and proceeded to evangelize his new faith.
There has been only one case of a decrypted unit being converted back to a living unit, Ossomer, but the reasons for this have not been stated. Having Wanda or arkenpliers leave the battlespace via portal may be a factor, but no other units have been affected, so another factor (being an Heir? Turnamancy undoing decryption?) must be involved.
- If, as has been suggested, the Arkenpliers extend Wanda's Croakamancy into the life element, could there be another stage above uncroaked and decrypted, one of true resurrection? If so, some, or all, of the factors listed above may have had a role in this change.
Despite the claim in the preceding paragraph, Ossomer did not become a living unit when he turned back to Jetstone; rather, the change in the colors of his clothes and armor came about because of his change in allegiance. This is shown by him turning to dust when he died, as a decrypted unit would, rather than dying and leaving a corpse, as a living unit would. This fact undercuts the above speculation regarding true resurrection.
Real World References
Decryption, in the real world, is used as the opposite of encryption, that is protecting data by turning it into a seemingly random sequence of symbols by means of a cypher and a key. Decryption is the opposite process, which takes useless gibberish and turns it into useful information, paralleling the process of taking a useless corpse and turning it into a useful creature. The same term is sometimes also used for removing desired content from protected sources (such as DVDs, music files and books). In this case, Wanda might have gained the ability to effectively remove the "DRM" from enemy units, allowing her to raise them without penalties and under her control. Alternately, the process of updating the MMORPG DDO contains a decrypting step, possibly suggesting the process is just an update to the units rules.
This makes the term a double pun, the 1st one being on "getting the unit out of a crypt".