Metal Slader Glory: Director's Cut (SFC) has been fully translated into English
Sonic Unleashed has been unofficially ported to PC (Windows/Linux)
An unofficial PC port of the Xbox 360 version of Sonic Unleashed created through the process of static recompilation. - hedge-dev/UnleashedRecomp
This has implications beyond just this game - the process of recompiling the Xbox 360 version led to the creation of two dedicated tools (XenonRecomp and XenosRecomp) that could be used for other games on the platform. (Theoretically, of course - I recall one developer saying it would likely take a considerable amount of modification for use outside of Unleashed, but it *was *possible.)
Two preview builds of Mega Man X7 have been dumped publicly

I’ve obtained two pre-release builds of Mega Man X7 to share with you today. The first is the U.S. Preview Version, which I’ve been searchi...

Specifically, one for preview events in early 2003 and one for that year's E3.
Video outline of scrapped content for Lego Dimensions

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Video overview of newly-released, very early 3DS game prototypes (mostly E3 2010 tech demos)

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Newly released prototype for Half-Life on Dreamcast (dated September 10, 2000) + a written history of the port

Presentation of an early prototype of Half-Life Dreamcast, with a behind-the-scenes look at its development by Captivation Digital Laboratories programmer Robert Morgan and Sierra game producer Jeff Pobst.

Day 2 of Hidden Palace's "NESMas" - 40+ prototypes dumped from the collection of the Nolan brothers (longtime NES collectors)
Hidden Palace has released 40+ NES/SNES/Genesis/Game Boy prototypes (with more to come)
Full E3 2010 trailer for what would become Paper Mario: Sticker Star

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This was discovered & posted earlier in the month - probably late posting it here, but I felt like it fit the site's purpose well.
New CodeBound dump: a very early prototype for Cartoon Network Block Party on GBA + 2 design documents

A prototype of Cartoon Network: Block Party for the GameBoy Advance, dated June 17, 2003. This prototype predates the final release by over a year.As this...

Maybe not the most exciting release, but game history is game history.
Newly-released Crash Twinsanity prototype

A prototype of Crash Twinsanity for the PlayStation 2.

Aero the Acro-Bat is getting rereleased on modern consoles on August 2

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Just the first game.
Infamous "kusoge" RPG Ancient Roman has now been unofficially translated into English
Live Wire will delist their Switch port of Mushihime-sama on August 10th
いつもLive Wireのゲームを遊んでくださり、ありがとうございます。 Nintendo Switch™『虫姫さま』につきまして、ライセンス契約の満了に伴い、『虫姫さま』ダウンロード版の販売を、2024年8月10日(土)をもって終了させていただくことになりました。 ▼販売終了日...
This is because their license from CAVE (the game's original development company) is expiring.
New from Hidden Palace: the last build and source code for the unreleased MD game Out of the Vortex

Out of the Vortex (Sep 13, 1995 prototype) Out of the Vortex (Source Code - Sep 13, 1995) BONUS: Hard Boiled (Jun 17, 1997 prototype) Hard Boiled (Jul 25, 1997 prototype) Hard Boiled (Aug 24, 1997 prototype) Discuss this release on our Discord server!

Internal development slideshow for Crash Bandicoot: The Wrath of Cortex
A slideshow for internal use of Crash Bandicoot: The Wrath of Cortex, detailing many of the game's new features. Includes early design sketches and...
RIQA , a cancelled N64 game, has had its ROM leaked online

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A previously-unpreserved demo for the Japan-only mobile phone port of Klonoa: Door to Phantomile has been saved
The largest campaign ever to stop publishers destroying games (by Ross Scott)

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A rare Rockman.EXE (Mega Man Battle Network) medal arcade game has been dumped

No April Fool's joke here. Another Rockman EXE arcade game has been successfully preserved! Medal Network: Rockman EXE has remained some...

Definitely planning to buy this sometime!
Excellent article! I hope the effort to preserve this game succeeds - I have a soft spot for hyper-obscure but interesting titles that are genuinely at risk of being near-entirely forgotten.
You're welcome!
Part of me feels like the health-as-timer mechanic was born from the developers approaching the game with arcade-style design in mind. That sort of thing works to make sure people don't play too long on the machine (a la Gauntlet or Wonder Boy), and while other games still retained it I don't think it fits well with the kind of game Mega Man turned out to be. (That said, I think the final product's completely useless scoring feature is definitely a holdover from this same line of thought.)
This is an excellent study! As idealistic as this may sound, I really do hope it becomes a landmark in video game preservation - hard, inarguable numbers making it clear that significant chunks of history are missing from the current gaming landscape.
I'm really late to reply, but thank you for doing this!