Monday, June 3, 2024

"EZ Web" Versions of Rockman EXE Mobile Games and Battler's Tower Preserved

Hey, Mega Man fans! This is RockmanCosmo, the leader of SciLab Secrets – the team working to preserve lost Rockman games released on Japanese feature phones (keitai). The past couple of months have been extremely eventful for Rockman keitai game preservation. Since December 2023, we have preserved nine previously-lost games, including Rockman DASH 5 Islands and both original Rockman EXE games. Today, I’m happy to announce that the SciLab Secrets team has preserved even more games: the EZweb versions of Rockman EXE Phantom of Network and Legend of Network, and a companion app for Phantom of Network called Battler’s Tower. We’ve even preserved phone wallpapers and ringtones! Read on for all the details.

What do you mean by “EZweb versions”?

Phantom of Network and Legend of Network were released on two competing Japanese mobile internet services: DoCoMo’s i-mode and KDDI’s EZweb. Capcom had their own gaming storefronts on each service, accessible through a monthly subscription. Both games featured an in-game currency called Battler’s Points (BP). Initially, players received 300 BP upon purchasing a game and 300 BP at the beginning of each month. However, each version of Phantom of Network and Legend of Network utilized BP in slightly different ways. Let's explore these differences in detail.

Phantom of Network was initially released for DoCoMo’s i-mode service in October 2004, with each story chapter being released bi-weekly and the story concluding by the end of December. BBS job requests cost 20 BP, creating a pseudo-paywall. In November 2005, almost a year after the story ended on i-mode, Capcom released the full game on KDDI’s EZweb service. This version charged 100 BP per chapter, a change from the bi-weekly distribution on i-mode, and BBS job requests were free. Instead, BP could be spent on wallpapers and ringtones, with users able to purchase additional BP using real money (e.g., 100 BP for 105 yen). Later in 2005, Capcom updated the i-mode release to include these new BP features, allowing users to purchase extra BP and use it for phone customizations.

Legend of Network, like Phantom of Network, was released on i-mode in October 2006. Capcom employed a similar monetization system to Phantom of Network’s EZweb release, with each chapter costing 100 BP. After a year of i-mode exclusivity, Legend of Network was released for EZweb in October 2007. As if there weren't already enough versions, Capcom re-released both games on i-mode in November 2009. In these versions, story chapters and BBS job requests were included with the purchase, making BP obsolete.

So, what versions has SciLab Secrets preserved so far? Back in December, we preserved the 2009 i-mode versions of Phantom of Network and Legend of Network. Today, we've preserved the sole EZweb versions of both games from 2005 and 2007, including the EZweb trial version of Phantom of Network. The original 2004 and 2006 i-mode releases remain lost to time, although their contents are virtually identical to the 2009 i-mode releases.

What’s so special about the EZweb versions?

There are a few minor differences from the i-mode versions! Curiously, HatMan’s Silk Hat attack in Phantom of Network’s EZweb release has a question mark on the front of the hats. In the i-mode version, the hats have the letter “H” instead. The EZweb version of Legend of Network has moving cyberworld backgrounds! You can view an example of it here (spoiler warning, this is footage of the final boss!). The net backgrounds are solid colors in all i-mode releases, including the 2009 re-release. 

What is Rockman EXE Phantom of Network - Battler’s Tower?

Battler’s Tower is a companion app to Phantom of Network, released in January 2005 for i-mode and in October 2007 for EZweb. It continues Phantom of Network’s story and functions as a Net Battle simulator. The story of Battler’s Tower incorporates elements from Battle Network 4. Notably, Yai, who was absent in both Phantom of Network and Legend of Network, has a speaking role in Battler’s Tower. Using save data from Phantom of Network, Battler’s Tower allows players to engage in Net Battles against other players’ MegaMan.EXE data, simulating a PvP mode. Additionally, players can fight Navi bosses in a time attack mode, with the addition of DS versions of these Navis -- a feature not present in Phantom of Network. Again, we have preserved the EZweb version of Battler’s Tower, but the DoCoMo version has not yet been found.

The Preservation Process

Our KDDI copies of the games originated from a Sony Ericsson W53S. The mastermind behind the dumping procedure was team member Kraze, who is highly knowledgeable about preserving lost EZweb games from KDDI phones. Having dumped multiple W53S phones in the past, he was very familiar with the archival process. Team member GoodTofuFriday executed Kraze’s instructions on the phone.

First, the phone was carefully disassembled to allow Tofu to search for JTAG pins on the phone’s PCB. This was a tedious process, involving many plastic clips and cables. Next, Tofu utilized a flashing interface called RIFF Box to dump the W53S’s NAND chip. He had to carefully solder wires from the RIFF Box onto the phone’s tiny JTAG test points. Kraze had already documented the exact test points, saving Tofu some extra effort.

Finally, Kraze analyzed the resulting firmware image with a tool by team member usernameak. The W53S used the Fugue FAT filesystem implementation, and usernameak’s tool transformed that data into a readable FAT16 disk image.

We were pleasantly surprised to find the games, downloaded wallpapers, and downloaded ringtones! The W53S’s owner had used some BP and bought 40 individual Rockman EXE phone wallpapers and over a dozen ringtones! You can download these preserved Phantom of Network and Legend of Network wallpapers here. They are on the small side due to the W53S’s small screen, but they’re great to have nonetheless. The phone’s owner also bought many EXE-themed ringtones, including several tracks from each EXE game! This means we have official ringtone renditions of popular tracks like “Final Transmission” or EXE6’s “Operation!” theme. You can download these ringtones here. You can listen to the audio files via Yamaha’s MCP-MA7 or MidRadio applications.

Are these versions playable?

Yes and no. First, let’s detail how these games differ from their DoCoMo counterparts on a technical level. Most EZweb games run on BREW, a different platform than DoCoMo Java (DoJa), which is used by i-mode games. Consequently, our preserved EZweb EXE games run on BREW. Unlike i-mode games, emulation is much harder to come by for EZweb games.

Despite issues with sound emulation, the i-mode versions of Phantom of Network and Legend of Network can be satisfactorily emulated through DoCoMo’s official DoJa SDK. In contrast, there is only one emulator for mobile BREW games, Melange, developed single-handedly by our own usernameak. Melange runs on early versions of Android and currently does not support sound. As of this writing, the EZweb EXE games cannot run on Melange. The trial version of Phantom of Network crashes upon launching, and the rest of the games have network checks upon launch. To circumvent these network checks, we need to create a local server and usernameak must add network support to Melange.

While this may come as disappointing news, it reflects the current reality of EZweb game preservation.

However, we managed to get some of the games running on original hardware! Team members Kraze and usernameak found a way to sideload games on a W53S – the very phone model from which the games originated. This is the first time any game has been sideloaded on a Japanese feature phone, making it a noteworthy achievement.

First, Kraze loaded custom firmware onto his W53S using the aforementioned RIFF Box. The custom firmware contains an application by usernameak called AppUI, which allows apps to be installed from a MemoryStick. Next, Kraze installed the EXE games onto the phone via MemoryStick. After modifying the files, Kraze was also able to remove the initial network checks from both Phantom of Network and Battler’s Tower.

However, Phantom of Network crashes upon entering a battle, and Battler’s Tower fails to boot past the title screen because it cannot retrieve certain game files. Kraze needs to do further analysis of the game files to get the full games to run properly, but this is a step in the right direction for sideloading on original KDDI hardware.

The future of SciLab Secrets

In three years, SciLab Secrets has preserved two versions of previously lost EXE games, a Rockman DASH midquel, and several Rockman minigames. What more could there be to do? A lot, actually! The EZweb versions of the EXE games still need to be properly emulated. The DoCoMo Rockman games have yet to be sideloaded on original hardware. Rockman DASH 5 Islands still needs an English patch. Additionally, many other lost Rockman keitai games, from the wacky Intuition! Rockman to ports of Rockman X4, are still out there.

Moreover, the SciLab Secrets team has made an impact that spans beyond Rockman keitai games. Our research and work have benefitted the preservation of other keitai games and increased the visibility of keitai game preservation in the public eye. Therefore, SciLab Secrets will continue to work and advocate for keitai game preservation! There’s so much more work to do, and I hope to give you more updates in the future!


  1. Wow. That's honestly a lot of work to preserve games. Pretty impressive.

  2. Very complicate and a lot of work. Keep up the good work. I can't wait to grab it soon!

  3. I don't know why an effort is made to use "keitai" (携帯) when it is literally just the Japanese word for cell phone. It's not like modern Japanese games like Fate Grand Order is called a sumaho game or something.

    1. It's to differentiate them from non-Japanese feature phone games, like Western flip phones. Writing "Japanese feature phone game" is a mouthful, so we've decided to use the term "keitai game" to refer to the same thing for brevity sake. This was done after consulting with Japanese speakers too.

  4. Glad to see the team is working as diligently as ever. Fantastic work on the recent achievements, and hoping that when you next put out an update that it carries even more good news.

    Thanks for what you do.


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