Popful Mail is a 2D platform game with several RPG elements - excluding the ability to level-up characters. The controls allow the player to jump, attack, open doors or treasure chests, and speak to another character. Additionally, the player can summon a menu to change some of the game's attributes, the current character, the current character's equipment, use or activate an item, read the game's status, save, load and quit.
At the start of the game, the only playable character is Mail; however, as the game progresses, Tatt and Gaw will be available, and the player may switch between them at any time through the use of the "character" option in the menu (except in the middle of dialogues). Each character has different attacks and armours, as well as differences in walking speed and jump. Mail is the fastest character, but is the one whose jump is lowest. Tatt is balanced—slower than Mail but faster than Gaw—and his jump is similarly in between. Gaw is the slowest of the three, but his jump and attacks are usually the highest.
The character encounters enemies as well as non-playable characters. Often, when encountering an important character, dialogue begins immediately, with the player having no control over it. These important dialogues are by default always voice acted: however, text accompanies them, and the voiced speech can be turned off in an options menu if so desired.
The character has 100 health points, and attacks from enemy characters diminish it according to the strength of the attacker. Similarly, all enemies have a 100 health point bar that has to be brought down to 0 for the enemy to be defeated. How much damage is dealt depends on the strength of the character, although an attack always causes the same amount of damage to the same enemy. The character also has a blue-grey bar that is depleted as a distance weapon or a magical attack is used. When the bar reaches 0, the character can still perform the weapon motion, but the magical or long range portion of the attack will fail. The bar regenerates quickly if given time to do so (if the character uses no attacks or switches to a melee weapon). Use of a distance weapon or magical attack while the bar is regenerating halts the regeneration, which resumes if no attacks that deplete it are made.
Each character can acquire up to five different weapons and various items. Each subsequent weapon is stronger than the preceding one, although the player may switch to any weapons possessed at any time if so desired, through the menu. Weapons include a sword, dagger, boomerang, staff, fireball, and claw. Items, different from weapons and armour, affect either the health bar or the character's status, or are plot devices. They may confer invulnerability at a price, stability in snow, or replenish health, among other things. They can be obtained from other characters, treasure chests, shops, or bosses (in certain cases are used for plot devices).
The game has a practical save game feature. Games may usually be saved and loaded at any point in the game (except during dialogues, world map travels, and the animated sequences); if a game that was previously saved in a room with a boss is loaded, the game resumes just before the battle, before the character has entered the room. The state of the game, including the hours played and the level, will be displayed. Three save slots are supplied, for storing up to three different states. The stages in the game consists of Elf's Forest, Golem Tower, and Muttonhead's Wind Cave.
Though portrayed differently from port to port, set in an unnamed fantasy world, a prologue tells of a grand legend related to the realm, of how long ago, three fallen gods of darkness known as the Masters of Evil attempted to lay siege to the mortal plane; they were known as Morgal, the Lord of Beasts, commander of the feral and the most voracious of monsters and beasts, Necroz, the Master of War, corruptor of men and the inciter of temptation and vice, and Olrga, the Overlord, the leader of the Masters of Evil and wielder of the most evil of magics. At the end of the great war that threatened all who lived in it, the Masters of Evil were sealed away in a floating tower far from the reach of anyone, and only three warriors, an elf, a human, and a dwarf, survived to tell the tale.
Into the modern day, the main character and local bounty hunter, Popful Mail, makes her rounds; eventually, her day escalates to the point where she squares off with her bounty, the criminal golem maker and technomancer, Nuts Cracker, into the nearby forest. Though defeated, Nuts Cracker's body manages to escape, as always, and Mail thus cannot claim any bounty. Frustrated once more, she off-putedly takes Nuts Cracker's head and wanders back into town. At the bounty post, she attempts to trade the head in for cash, but like with many who have sought to capture Nuts Cracker before her, duplicates of his head are all they could retrieve, making the attempt a failure. Instead, however, she learns of a new bounty and becomes reinvigorated when she spots a 2,000,000 gold reward poster for the wizard turned criminal, Muttonhead, near the post. With sword in hand and hope in heart, Mail makes leads into the nearby forest for clues. Eventually, her quest to undertake the biggest catch of her career, will turn out greater, more perilous, more dangerous- yet more important, and even more rewarding- than she imagines.The main character, and the one with whom the player begins, is Mail, a female elf bounty hunter who hasn't had much luck lately. Mail's main target, Nuts Cracker, always seems to escape after she defeats him. Mail has red hair; her pointed elven ears stick outward from her head, as in the Japanese convention. Her personality is rather confrontational, and she is never drawn as humorous or morose. Her main and starting weapon is a sword; she can acquire a dagger and boomerang as the game progresses.
Tatt is a magician, a former apprentice of Muttonhead. He chases after his master, who has left him and his fellow students, in order to find out why and ultimately dissuade him from his path. Tatt is kind, polite and a bit timid, and is sometimes ridiculed. He meets Mail in the first level. His main weapon is a magical staff. He wears a red hat, perhaps to present him as neither a black magician nor a white one.
Gaw is a small, round, winged, cave-dwelling purple creature. He almost identical with all the others of his species, who call themselves "Gaw" as well. Gaw itself is often an interjection all gaws use when speaking. Mail and Tatt meet Gaw in the second level, the Caves, but Gaw joins them later. Gaw's first main attack is a fireball; subsequent attacks include a tail swipe and clawing.
Nuts Cracker, the first villain seen in the game, is the leader of a dangerous criminal gang known as the Gingerbread Grifter Gang. He specializes in manufacturing explosives, especially exploding dolls. Appearing to be human, Nuts Cracker instead is fashioned like a nutcracker, wood and all, implying he had transformed himself into a machination. He also speaks in a goofy Italian accent. When defeated, he will often throw his head—which then explodes—while his body runs away. Mail has been trying to catch Nuts Cracker for a long time and has faced him on many occasions, but he always escapes.
Muttonhead was formerly a well-known and respected magician before unexpectedly disappearing from public view and turning to crime, a move that left his apprentices puzzled. He is dangerous and his goals unknown. A 2,000,000 gold bounty is offered for his capture.
Slick is an elf acquaintance of Mail's. He often wants to tag along with Mail on her adventures, which, along with his bad jokes and obnoxious demeanor, annoys her to no end. He often causes more trouble than he solves, and is especially infamous for his use of home-made bombs, which his grandfather taught him how to make.
Glug is a nice dwarf from the mines. Unlike everyone else, he enjoys Slick's company and they are both friends. It is hinted that Glug suffers from mental problems as a result of a strong knock on the head, which might also explain his naiveté and short memory.
Falcom developed the NEC PC versions of Popful Mail with features used in previous games in the company's Dragon Slayer and Ys series. They use the battle system of Ys, magic attacks like those of Ys II, and a side-scrolling view similar to that of Ys III. Characters react with pain when they fall from high places, as in Dragon Slayer IV (released as Legacy of the Wizard in North America). The original releases incorporate features from the popular game Xanadu (Dragon Slayer II) as well.
Gaming magazine Electronic Gaming Monthly reported rumours of a new game in Sega's Sonic the Hedgehog series called Sister Sonic, which was to be shown at the Tokyo Toy Fair in June 1993. The game, which ultimately did not appear in the Fair, would have been a remake of the PC Popful Mail using Sonic characters in place of Mail's. After Mail fans petitioned against the remake, "Sega Falcom" (the alliance between Sega and Falcom that would have made Sister Sonic) instead created a version of Popful Mail for the Sega CD, retaining original characters Mail, Tatt, and Gaw.
Working Designs localized the Sega CD version for North America, and made several changes and adjustments to the game. Enemies were made more difficult, downsampling and variable bitrates were used to compress the game's sounds from full 44.1 kHz CD quality to fit on the game disc, Except in animated sequences, waveform analysis was used to make characters' mouths match their dialogue. Two teams worked on the English translation for four months.
The Sega CD version received a score of 31 out of 40 (average 7.75 out of 10) from Electronic Gaming Monthly. They especially praised the game's "cinema scenes". GamePro likewise gave their greatest praise to the cinema scenes and extensive voice acting, saying they "add great color to the game, setting these quirky characters apart from the standard mold of RPG heroes and villains." They also commented positively on the game's linear, undemanding gameplay. Retro Gamer included it on their list of top ten Mega CD games.
Falcom used Popful Mail and its characters in various other media. The company created two Mail drama CD series published by King Records: Popful Mail Paradise (ぽっぷるメイルパラダイス), a series of five CDs released between 1994 and 1995; and Popful Mail The Next Generation (ぽっぷるメイル－ザネクストジェネレーション), two CDs released beginning in 1996. Falcom created Tarako Pappara Paradise (TARAKOぱっぱらパラダイス), another drama CD published by King that features Mail, on 22 November 1995. GameMusic.com sells Tarako and Paradise dramas 2 through 5 in the United States.
As with Ys IV, an attempt was made to pitch an anime OVA based on the game to various anime studios, but failed to cite interest with the pilot. The promotion video is all that remains of the idea, which imagines Mail and friends finding themselves in real world Tokyo upon fighting a new foe.
Mail and Gaw, along with other Falcom characters, would return as secret "Masters" in the 1997 Falcom game Vantage Master. Mail's outfit was featured as downloadable costume for Tina Armstrong in Tecmo Koei's Dead or Alive 5: Last Round.