With the recent release of HENkaku many PlayStation Vita sceners not content with simple homebrew desired to play PS Vita VPK game backups... enter Adventure Time: The Secret of the Nameless Kingdom! 
If you dodge Sony's latest PS Vita 3.61 Firmware Update or simply PSProxy Bypass it and head over to Pastebin.com you'll see the following, which appears to have been dumped by someone who calls themselves HF:
Adventure TIme - Very first vita backup.vpk (176.18 MB)
Adventure time psvita, never released game (dumped from devkit)
Install from Vitashell 0.7
trophies work, enjoy the ban
-- hf
While there is an official PS Vita VPK Showcase and VPK Mirror, these repositories primarily consist of Compiled PS Vita Homebrew with none containing commercial retail PlayStation Vita games playable as VPK files.
According to Yifan Lu on Reddit, to quote:
"This is not backups/backup. This is good ol' fashioned game leak from a developer that went under. Here's the original source: http://assemblergames.com/l/threads/psvita-prototype-thread-dont-expect-much.61282/
Basically someone bought a test kit from the gray market and it happened to have this game installed. These kits are used by game development companies to develop games so of course there's no DRM on them.
When the company goes under, the kits are supposed to be returned to sony but sometimes they get sold without sony's knowledge. Don't expect this to happen often."
Based on some other Reddit comments, the Adventure Time: The Secret of the Nameless Kingdom VPK leak does work on PlayStation Vita handhelds with PS Vita trophies as the Pastebin (above) indicates.
If you dodge Sony's latest PS Vita 3.61 Firmware Update or simply PSProxy Bypass it and head over to Pastebin.com you'll see the following, which appears to have been dumped by someone who calls themselves HF:
Adventure TIme - Very first vita backup.vpk (176.18 MB)
Adventure time psvita, never released game (dumped from devkit)
Install from Vitashell 0.7
trophies work, enjoy the ban
-- hf
While there is an official PS Vita VPK Showcase and VPK Mirror, these repositories primarily consist of Compiled PS Vita Homebrew with none containing commercial retail PlayStation Vita games playable as VPK files.
According to Yifan Lu on Reddit, to quote:
"This is not backups/backup. This is good ol' fashioned game leak from a developer that went under. Here's the original source: http://assemblergames.com/l/threads/psvita-prototype-thread-dont-expect-much.61282/
Basically someone bought a test kit from the gray market and it happened to have this game installed. These kits are used by game development companies to develop games so of course there's no DRM on them.
When the company goes under, the kits are supposed to be returned to sony but sometimes they get sold without sony's knowledge. Don't expect this to happen often."
Based on some other Reddit comments, the Adventure Time: The Secret of the Nameless Kingdom VPK leak does work on PlayStation Vita handhelds with PS Vita trophies as the Pastebin (above) indicates. - From 12thedata12 on Reddit: "Its a near-retail release. I haven't played the finished release but I have seen some graphical inconsistencies within this version so they might have been removed before launch but this is very close to a finished version."
- From JJSec on Reddit: "Can confirm it works. yes does have trophies but i ain't connecting to PSN again anytime soon.
But if unreleased and dumped from devkit without encryption, it won't make any difference to the backups circuit, more the proto/unreleased community (which i happen to have more interest in anyway)"
- From Bishibazu on Reddit: "I don't know if this is going to be useful but, after I tried to open the game (in airplane mode) to test it, I uninstalled before getting any trophies and with VitaShell I also removed the Trophy related files in ur0:\ In fact after re-opening the trophy application the game disappeared. Is this enough or not to delete every trace?"
