Arguably the most popular game in the first batch of arcade releases, Mappy follows the formula of other succesful titles of the time, including Namco's own Pac-Man - Your job is to collect objects while avoiding all enemies. The premise is that a gang of cats, called the Mewkies, have stolen a bunch of goods, such as electronics and paintings, and hidden them in their elaborate mansion. As Mappy, a mouse cop, you have to go in and get all goods back while cleverly avoiding the Mewkies and their leader, Nyamco (Goro in the US).
Like most arcade games the game is divided into rounds. There are 15 rounds total, 4 of which are bonus rounds. If you manage to clear them all, you return to the first, but the difficulty will be slightly increased.
The mansion is quite strangely designed. Each normal level has six floors, but there's no stairs whatsoever - You move between floors by jumping on strangely placed trampolines. The Mewkies have to use the trampoline as well, but the good news is that when you're both on it, you can't be killed by them. The bad news though is that you can't keep bouncing forever - If you bounce too many times without getting off, the trampoline breaks and you fall to your death!
Of course that's not the only way to avoid getting killed - Every stage also has a number of doors, both normal ones and flashing "microwave doors", which you can use to temporarily stun the Mewkies. Slamming a door open in their face will knock them back, while opening a microwave door sends out a shockwave all the way across the level - Any Mewkies hit with it will be blown out of the stage completely, although they'll return not too much later.
Like any good arcade game there's bonus points to earn for the score freaks. For example, every item you have to retrieve has a point value - But if you manage to stay alive long enough, the more items you collect, the more the later ones will be worth. Therefore, if you want a lot of points, you should grab the lowest valued items first and the highest valued ones last.
Nyamco, the leader of the Mewkies, can sometimes also hide behind an item for a short while - If you run by and snag the item while he's hiding you'll get a bonus as well, but be careful, because if he happens to start moving again as you move in to grab the item you're a goner!
Then there's the bonus stages - In these you can take a short breather as there's no Mewkies to worry about. Instead you are presented with a cleverly designed maze of trampolines, littered with balloons. Obviously, the objective is to pop as many as you can, but good players will figure out a way to get every single one of them, earning another bonus.
As Mappy is a score-based game there's no continues - You can pump in as many credits as you want, but lose all lives and it's back to the first round with you! The VC version of Mappy includes two configurable options - You can set the amount of lives you get per credit, and you can set the point requirement to earn extra lives (Or you can disable extra lives completely!).
The game might not be as popular as Pac-Man or other Namco franchises, but as it stands it's still quite addictive and fun, even if it does get hard fairly fast. For 500 points you also get the best version of the game Namco has made, so what's not to like?