Even in the shady underworld of the ROM hacker, there’s a lot of innovation and high-quality work that improves already excellent games. Sometimes this is only tweaking, but often these hacks completely change the gameplay experience, creating effectively new games. Here are some of my favorite ROM hacks:

To show off the functionality of the great Super Mario World editor Lunar Magic, the creators have also released a couple of complete conversions for Super Mario World, with custom graphics, levels, and even whole new block types. Highlights include some great-looking overlapping blocks and a wealth of new gameplay.

A nearly complete conversion of the classic original NES Metroid, this was almost 90% done as of press time. One of the most interesting things about this hack is that the page contains all the earlier versions of the IPS patch as well, so you can see how the conversion gradually takes place over multiple save files. Besides new graphics, levels, Samus sprites, and improved gameplay, the title screen and introductory text have changed as well, so this is almost a total conversion.

An extremely complex, faithful update hack of the NES Legend Of Zelda, this hack includes a completely redesigned overworld and dungeons. The beach has even changed to another overworld location entirely, and the wave sound effects moved with it. Elsewhere on the site, the hacker also points to some very helpful ROM data locations (http://www.cg-games.net/challenges/zeldac/zeldarom.txt) for any wannabe hackers.

Making a distinct change from all those platformers, this is a conversion of the classic bat n’ ball NES title Arkanoid, with a complete set of 33 new levels. Although significantly and fiendishly trickier, this is a simple block rearrangement hack. It’s also one of the purest and most fun hacks, simply because playing through Arkanoid in a linear fashion throws up the same levels over and over. This new level set is a refreshingly addictive change; it’s even more fun if you can find a NES Arkanoid controller and a way to use it!

Once upon a time, the ROM modification scene voted this the best ROM hack ever. It’s easy to see why; this is a complete level hack of the gigantic NES title Super Mario Bros 3 that includes some familiar territory, but also switches powerups for bad guys in strategic places and changes some level blocks significantly. Be sure to check out the lengthy third-party walkthrough (http://www.cg-games.net/challenges/smb3c/walksmb3c.txt), which includes detailed descriptions of all the changes.

While it’s exciting to patch and play level hacks from the original ROM, it’s more interesting still to create your own. A good starting point is, again, Zophar.net’s comprehensive utility compilations (http://www.zophar.net/utilities/level.html), which includes a mass of over 100 editors for various classic consoles.

Not all of them are easy to use, and some date from the heyday of emulation hysteria in the late ’90s, when DOS utilities were much more common, so beware of incompatibilities with newer versions of Windows. Overall, there’s a massive amount of working, good-quality editors. Here are a few of the highlights:

By far one of the most spectacular, fully formed level editor hacks of all time, this utility features a comprehensive Windows-based graphical interface for one of the best games of all time, the Super Nintendo title Super Mario World. The hack is so advanced that the authors have even added the ability to make completely custom graphics and a full overworld editor (for changing the map screen that allows players to move between and choose sidescrolling levels). Finally, they even imported the breakable brick concept from Super Mario 3 into the game.

(http://www.zophar.net/utilities/neslevel.html)

Mixing things up a little, this rather marvellous little editor for NES Rush N’Attack (also called Green Beret) allows palette, enemy and level edits, and even makes it easy to create IPS patches, something that some other more rudimentary ROM editors don’t. The Windows tool comes with optional source code.

Wow. The scene, based on the classic SNES game Earthbound, is particularly committed, but this amazing collection of tools allows the wannabe hacker to edit text in detail, even adding and changing cut-scenes, shifting the visual look of sprites, and expanding the ROM size to add extra information without running out of space. It also sports a comprehensive map editor. There’s more knowledge here than in many other games combined, so there’s plenty to work with.

Released by SnowBro Software, this comprehensive NES Metroid hacking tool allows tile and map rearrangement, as used in the Metroid C hack detailed earlier. It’s also worth noting that the author has the source code for the tool available on his site (http://www.stud.ntnu.no/~kenth/).

It may be simple, but if you just want brightly colored, fun results, editing the brick palettes and positioning for NES Arkanoid via the DOS editor ArkEdit may be the ticket for you.

Unfortunately, level hacks are sometimes given a bad name because of their similarity to the often asinine sprite hacks found randomly all over the Internet during the height of emulation fever. (You might remember Super Mario, with Mario turned into a Teletubby, and similar or more scatological randomness.) A site called I-Mockery has made a most amusing pastime out of poking fun at these lame sprite swaps (http://www.i-mockery.com/romhacks/).

Fortunately, the highlighted hacks described here show that there’s a really creative scene out there, hacking existing code to create entirely new gameplay experiences. Perhaps in the future, just as the Activision Classics GBA compilation includes homebrew Atari 2600 titles, classic compilations of console games from the NES or SNES could include the best level hacks as official releases. That’s a pipe dream, sure, but perhaps a worthy one.