These overlays (sometimes known as bezels) display art on top of the game you're playing. To use them, you need a PC or Raspberry Pi (or other compatible system) running some version of MAME and the associated game software, as well as a widescreen (16x9) monitor mounted vertically. To display the overlay while playing a game, download the artwork file for that game overlay (it must have the same filename as the game), place it in the Artwork folder within your MAME directory and launch the game. (For instance, the software for the game Magic Sword is called msword.zip, so it requires a file in the Artwork directory also called msword.zip.)
All overlays are 4K resolution (2160 x 3840), and listed dimensions are for the game screen, relative to a 4K vertical monitor. The actual game screen size will depend on the resolution of your monitor.
Most of the overlays include multiple presets that let you choose the size of the game screen, access a "dark" version designed to look more like a dark arcade, and sometimes other options. To choose a preset, press Tab while running the game to bring up the MAME menu, select Video Options, and select a preset from the list.
Some overlays include Curved presets designed with a curved screen port, to better simulate the look of a CRT monitor. These presets work best if you are using a geometry shader that adds a curved look to the game screen. For an optimal experience, you may need to adjust your shaders to match the curvature of the screen shape in the overlay. If you are not using a geometry shader, you are using a shader that adds a curved bezel, or if you prefer a rectangular screen port, choose a Straight preset where applicable.
Boot Hill took the head-to-head action of early arcade games like Pong and transformed it into a simple but effective two player combat game. Itself a sequel to Gun Fight (adapted from Taito's Western Gun), the game updated its predecessor's concept with a colorful illustrated backdrop that added visual appeal and a feeling of depth, and two-axis movement, which added tactical depth to the game. The game uses two joysticks, one for movement and one for aiming and firing, a control scheme that was unusually deep for its era. Moving wagons and cacti provide a small amount of cover, but ultimately it's just two cowboys, and this town isn't big enough for both of them.
Cruis'n USA was a part of the 3D renaissance in 90s arcades, when more powerful arcade hardware was still able to outperform the growing console and PC market, and featured relatively realistic 3D graphics along with a sit-down driving experience. Developed initially outside of Midway by Eugene Jarvis's team before moving inside the company, the game was part of an ill-fated deal with Nintendo that had the game claiming to run on Nintendo hardware, but the subsequent Nintendo 64 port failed to capture the arcade thrills. As recounted in the 2020 documentary Insert Coin, the game was seen as a more casual (and thus derided) experience, but it became popular with women gamers and outperformed competitor Sega racer Daytona USA in sales.
Killer Instinct was a groundbreaking fighting game for its time in numerous ways: it used 3D-rendered graphics in a more extensive and dynamic way than most games up to that time, in addition to introducing a variety of elements to the fighting genre, including automatic combos, combo breakers and the continuation of character life bars between rounds. Developed by Rare, the game was a part of a partnership between Nintendo and Midway parent WMS to create and market arcade games that would then be ported to Nintendo consoles, particularly the Nintendo 64. Despite its ties to family-friendly Nintendo, the game features a fair amount of violence and gore, including finishing moves reminiscent of the popular Mortal Kombat series. Killer Instinct dominated arcades during its time and spawned one arcade sequel and a later Xbox re-imagining, not to mention a full-length documentary.
The sequel to Rare and Midway's groundbreaking fighting game with 3D-rendered characters, Killer Instinct 2 refined and expanded upon the gameplay system of the original game in numerous ways. KI 2 adds a Super bar which enables more powerful attacks, an expanded combo system based around "autodoubles," throws and parries, easier combo breakers and a remixed roster of characters. The backstory has the returning cast sent back in time and fighting to defeat the evil Demon Lord Gargos, with varying endings depending on which characters they defeat with finishing moves.
It is probably safe to call Mortal Kombat the most controversial game in arcade history — plenty of other games have attracted attention and caused offense, but few inspired US Congressional hearings. Mortal Kombat added a darker, more serious tone and graphic, bloody violence to the burgeoning fighting game genre — a distinctly different direction from Street Fighter II and its clones that would make it a runaway success, and even help push the revival of arcades in the 90s. The game's graphics pushed boundaries as well, using video capture to create a look with surprising realism for its time, a technique that would go on to power NBA Jam and other Midway games. The violence attracted the crowds, but the game's air of mystery, including its Chinese mythology-inspired backstories, secret moves including the series-defining Fatalities, secret characters and other elements made it irresistible to its largely teenage, largely male audience. The game spawned three arcade sequels, numerous console sequels and ports, two somewhat questionable movies, comics, music, TV shows and even a live touring show.
Mortal Kombat II expanded upon the success of the original with multiple new characters, a continuation of the first game's plotlines, a refined fighting system and more. In addition to improving the graphics, making the gameplay more aggressive and attacks more varied and powerful, the sequel introduced a wider range of finishing moves — new Fatalities, including two per character, as well as stage-based Fatalities and humorous Babality and Friendship finishing moves (a relatively rare instance of a high-profile game parodying its own gameplay). Mortal Kombat II was an even greater success than the original, in arcades as well as on consoles, though its notoriety led it to be banned in Germany and helped usher in game rating systems.
Continuing the spine-ripping success of its two siblings, Mortal Kombat 3 introduced a run button to allow players to quickly close the distance to their opponent, coupled with a run meter, as well as pre-programmed chain combos that cannot be interrupted. The game's stages also feature multiple levels, accessed by knocking your opponent through the ceiling or floor to continue the battle on a new stage. In addition to the previous games' finishing moves, Mortal Kombat 3 introduced Animalities, finishing moves that transform your character into an animal before killing your opponent. The single player mode also includes the ability to choose a skill level, and players can enter a Kombat Kode to modify the gameplay or access hidden characters.
Mortal Kombat 4 marks the series' first foray into 3D graphics, which were fast overtaking the 2D video capture-based graphics Midway and the Mortal Kombat series were known for. In terms of gameplay, MK4 features essentially the same formula as previous games in the series, with 15 playable characters and the run button and combo system, though the transition to 3D caused the gameplay to be somewhat slower and the game didn't feature true 3D gameplay. MK4 also introduced a weapons system accessed with a button combination, as well as an upper limit on possible damage with one combo, and simplified the Fatality system to remove the series' less serious elements. As with other early 3D games from the late 90s, the game's 3D graphics seemed groundbreaking at the time, but have arguably not aged as well as the visuals of the 2D versions (that may be nostalgia talking, however).
The story of Ms. Pac-Man is worthy of a documentary, which it got as a part of Netflix's High Score series (definitely worth watching). Though it was seen as a proper sequel to Pac-Man, the game was actually created by an upstart American company as an add-on board for Pac-Man cabinets, which they sold to Pac-Man's US manufacturer Midway. Ms. Pac-Man expanded upon the original's female fanbase, and added numerous improvements to the original game's formula, including multiple mazes, updated sound effects and graphics and semi-random ghost movement designed to prevent pattern memorization. The game became a huge hit in North America and is often considered superior to the original.
NBA Jam took arcades by storm in 1993, creating one of the first arcade mega-hits of the 90s and cementing Midway as even more of an arcade heavyweight. In addition to updating the player roster, Tournament Edition tweaked the formula to add three players per side (two can be active at once), expanded player stats, a wide range of cheats and humorous hidden characters (ranging from Mortal Kombat characters to Bill Clinton) and Tournament Mode, which banned cheats and challenged players to beat all 27 NBA teams.