Felix the Cat is a very, very old fictional character, having been around since the end of World War I and perhaps even longer than most other cartoon characters that managed to last into the remaining quarter of the 20th. century and perhaps beyond. However, there were a lot of anthropomorphic animals to be had when the Warner Brothers and Walt Disney made their marks in the entertainment, such that Felix was in danger of slipping into obscurity.
It was not until 1953 that Felix got his perhaps most recognizable trademark, his "Magic Bag of Tricks" that can store a preposterous number of equally ludicrous items. The Bag was for all practical purposes instrumental in re-branding Felix.
In fact, Felix's revival in the mid-20th. century may have even inspired the creation of other fictional characters who also have similar "Magic Bags", that are otherwise known as fictional containers which can contain improbable amounts of stuff.
It would not be long before some Japanese game-makers noticed that peculiarity - the design of a certain robot cat with a pocket-dimensional pouch may have been inspired by Felix's own doohickey after all - and also the potential for making money off Felix the Cat's popularity.
Hudson Soft (of Bonk fame) noticed this, and the convenience of the designs of Felix the Cat's later incarnation with respect to crafting a video game protagonist. Felix the Cat, for the GameBoy (and the NES), was the resulting platforming game, based on the Felix the Cat TV series from the latter half of the last century.
The game starts with the usual premise of Felix's nemesis, The Professor, coming up to no good again. Specifically, this time he has kidnapped Felix's lady friend, the simply-named Kitty, likely in an attempt to ransom her for Felix's Magic Bag.
But of course, that's just an excuse for the game having to put Felix through a bunch of platforming levels while defeating enemies with deft jumping and quick use of the contents of his Bag.
Felix starts out pretty much like any other platforming protagonist. He moves along a side-scrolling level, can jump a modest height, and has a basic attack for eliminating enemies (typically knocking them out of and off the level).
Felix's goal in every level is typically simple: he has to reach its end before a timer counts down to zero. In addition to hoofing it to the end of a level, the player can also have him retrieving collectibles that look like one of Felix's lesser known feline friends having been trapped in floating bubbles.
Collecting these will feed a counter labeled with the letter "M" (likely the initial for "Magic"). Reaching the threshold of 100 grants him, in typical platformer-game fashion, an extra life.
These collectibles may also produce special power-ups when they are collected, though these power-ups enter the game world at where the collectibles once were, i.e. they are not automatically obtained by the player. These power-ups also appear to be affected by gravity.
(In other words, the player can lose the power-up to the usual vagaries of platforming games, such as bottomless pits. This game design is a little bit inconvenient, considering that the player already has expended the effort to retrieve the aforementioned collectibles.)
This special power-up allows Felix to upgrade his basic jack-in-the-box (or -bag) punching glove into another attack that is more expedient and more powerful. In addition, his appearance and even animations will also change. Every power-up of this sort will further upgrade his attacks and his countenance, eventually culminating in a heavy vehicle with a powerful attack.
The nature of forms and attacks that Felix can use changes according to the design of the level. For example, he may have to fly instead of trudging around along the ground, and even swim for underwater levels. For these levels, Felix has access to entirely different forms, each with their own special modes of attack.
Unfortunately, not all of the attacks that Felix has are handy to have. For example, his "ultimate" form for land-based levels, which is a tank, has an attack with a peculiar trajectory that is just not useful outside of boss battles, while Felix's form before the tank is practically a catch-all due to its simple ranged attack.
One can say that the game designers at Hudson may have been a bit over-reaching in their ideas for Felix's attacks, e.g. they may have been carried away by the themes of Felix's Magic Bag of Tricks.
Fortunately (or unfortunately), the player can attempt to stay in convenient forms by having Felix run into enemies. Like most other platformer games at the time, enemies need only defeat the protagonist by having the protagonist carelessly coming into contact with them or their projectiles. In this game, if the player does so, Felix's form drops one level.
The player can also manage between forms by simply having them eventually run out of "energy", represented by a meter consisting of heart-shaped icons. Every form has a temporary shelf-life, and will eventually degrade to a lower form over time unless the player collects power-ups in the shape of milk bottles (which will recharge the meter). In his basic default form, Felix is vulnerable to being K.O.ed.
The game designers could have introduced some level designs that take advantage of these different forms and even re-designed them so that they can be used to solve special puzzles, but they did not. This is a minor complaint, but it also felt like they had missed an opportunity to make the game more interesting.
Still, the game designers had focused on what made Felix the Cat a unique character right until now: his Magic Bag and the stuff in it.
Throughout every level, there are special objects that appear to look like bigger versions of Felix's Bag. Reaching this allows the player to enter areas of the level with bonus collectibles.
In addition to the counter for collectibles, the player also has a score counter, which can be increased by doing the usual things that platforming protagonists do: retrieving collectibles and power-ups, defeat enemies and reaching the end of the level to cash in any remaining time. Reaching score thresholds, of course grants the usual rewards of extra lives.
Felix the Cat is indeed quite an easy platforming game, especially if the intelligence of the enemies in this game is considered.
Enemies in the game are mostly creatures or objects based on those pulled from the TV show, or are otherwise completely new sprites. There appears to be a decent variety of enemies, though most of them are really unremarkable in both design and appearance. Moreover, all of them are of the usual sorts to be found in typical platforming games: static turrets who just sit in place and fire projectiles in a single direction, sentries with a fixed, never-changing patrol path (unless the player has them eliminated) and enemies who single-mindedly travel in just one direction.
Virtually all of them are easy to avoid and defeat.
The only ones which give any challenge - no matter how miniscule - are the bosses, who are usually the antagonists in the TV series. Much like Felix, they resort to preposterous devices to attack Felix with. However, they are also much like typical platforming video game bosses of the time: predictable.
This would have been acceptable, but the bosses - and Felix - are hemmed into an arena that is very, very small. Considering that the bosses tend to have fixed paths of navigation and that Felix is a lot more agile than any of them, Felix has the advantage in just about every boss fight. Moreover, these arenas tend to have cover that the player can take advantage of, or other kinds of crutches that the game designers included.
In fact, the last boss battle, which takes place in a large arena and against a boss with tremendous mobility, the game designers have deliberately included "bonus" areas where players can restock on power-ups.
Coupled with the mostly idiotic goons of the game, the game is tremendously easy for any player who practices sufficient carefulness. This game design was of course a deliberate one that was intended to capture younger players, but the game simply lacks any option to increase the difficulty of the gameplay for additional challenge.
The game designers do however compensate for the boredom that could have been brought about by the ease of gameplay with a variety of levels, such as the aforementioned ground-based levels and aerial ones. There are also underwater levels (which weigh down Felix's sprite with more inertia) and levels set in space (which will have the moving-screen mechanic found in typical space-based shoot-'em-ups at the time). These levels certainly pay homage to the various adventures that Felix had in unseeming places in the TV series.
The foreground of every level takes center-stage. There are platforms floating in mid-air (or suspended in water, for that matter), with all sorts of other decor that one can expect from a TV series that gave personification to even things such as bricks. The background, however, looks bland and there are plenty of repeated motifs, such as clouds resembling Felix' lady friend for levels based on Earth-like locations or nebulae resembling his lady friend for levels set in space.
Visually, the game looks great and would have done justice to the art direction of the TV series. However, poorly generated 8-bit soundtracks would come across as more annoying (especially to fans of Felix who knew better music themes) than doing justice to the series. On the other hand, to Hudson's credit, they are still quite upbeat, as befitting the theme of excitement that Felix's show has.
The sound effects sound whimsical, as befitting Felix's cartoon franchise, though they do sound like they had too much 8-bit straining. Perhaps the worst example is the laughable (pun not intended) 8-bit version of Felix's trademark hearty laughs that players hear at the end of every level.
In conclusion, Felix the Cat for the GameBoy may appear to be another typical platforming game with little unique designs (other than its license) to put it above the rest, but it is still a fun game that pays homage to the more whimsical themes of Felix's franchise.