Super Mario Brothers became a gold mine for Nintendo after it came; it was plenty able to sell Nintendo's systems on its own. Therefore, it was not surprising that Nintendo would attempt to try to sell its first hand-held system, which was the Game Boy, by having a Super Mario game as a launch title.
The first impression that a skeptical industry watcher would have of this GameBoy title was that it was a straight port of the NES game. After all, the NES title was an 8-bit game, and the Game Boy was an 8-bit platform; a direct port would have been easy.
However, if one plays the game, he/she would find that while the fundamentals of this Game Boy title are the same as those for the NES version, the content is very much different.
The graphics would have been the first noticeable difference. The original Game Boy was, of course, a wholly black-and-white affair from the perspective of visuals. Thus, Nintendo's technique/trick of using colours to present Mario's vibrant and fictional world in the NES version would not work here. Instead, Nintendo had put in a bit more effort into actually creating background images to furnish levels with. The background images had been rendered with little shading-in, while the foreground objects have plenty of shading across the grayscale palette to inform the player that these objects can be interacted with.
However, it has to be pointed out here that the background images also happen to look very, very simple. Trees are rendered with single-pixel curves and lines, pyramids are mere triangles in the backdrop and clouds are static. Worst of all, the background images seem to be cut-out completely when the player character reaches the end of the level, which is some kind of steel edifice with two doorways (one at the top, one at the bottom) and which appears to be shared by all non-boss levels, regardless of their themes.
Fortunately, the sprites and textures in the foreground are not as simple-looking. Lack of colour notwithstanding, they are definitely a notch above than those in the NES Super Mario Brothers; there are more animation frames and more detail. Of course, the lack of colour could have been a relative down-point.
The second deviation that the player would notice is the narrative difference. Bowser a.k.a. King Koopa is not Mario's nemesis in this game, but rather it's a certain "Mysterious Spaceman" by the name of Tatanga. Nevertheless, like just about every nemesis of Mario thus far and in the future, they have a knack for kidnapping a princess and forcing Mario to divert himself away from his usual plumbing jobs across the various (fictional) Worlds to save the hapless monarch.
(The Princess in this case is Princess Daisy, who is the ruler of the world of Sarasaland and makes her debut in Mario canon in this game.)
Of course, said enemy of Mario had to drag the portly plumber through a bunch of regions, starting with an Egyptian one up to his domain, which is in the sky (which does not exactly match his title of "Spaceman"). Each region consists of a few levels that, like the ones in the previous Super Mario games, have plenty of floating platforms for Mario to navigate, bricks and metal cases for him to smash, and enemies for him to bop and stomp.
Speaking of bricks, the World of Sarasaland consists of materials that are very different from those that make up the Mushroom kingdom. Most of them are square bricks, but there are also bricks with stripes, what appears to be steel ingots and such. The impression that a discerning player would get is that Nintendo is trying to compensate for the lack of colour with different shapes and patterns for these materials.
(There is even an Oriental-themed level with repeated Ulam spirals, which was a staple pattern in 8-bit games with Oriental themes at the time.)
The GameBoy did not have the same hardware as the NES, and this shows in the physical scope of levels. Where Super Mario Bros had levels within levels and even hidden sub-levels for the player to discover, as well as levels that span more than one screen in height, Super Mario Land does not enjoy as much design work. The result is that Super Mario Land feels more linear and hemmed in.
Many levels appear to share the same kinds of enemies that Mario has to face, regardless of their themes. Recurring enemies include the Goombas and the land-based Koopas. Of course, most of these repeatedly used enemies happen to be icons of the Super Mario franchise, but they would have been a disappointment to some who had expected Nintendo to put more effort in having every set of levels be a completely different experience from the others.
Otherwise, the other sorts of enemies appear to be unique to that region of levels. For example, the Egyptian levels have Sphinxes, who act like turrets, and the Cave levels have spiders that hang off ceilings and (somewhat) block off Mario's path.
The biggest disappointment in enemy designs can perhaps be found in the bosses. Thematically, they are no longer just an angry Bowser being repeated over and over for every region, but are instead lieutenants of Tatanga who are intent on stopping Mario's quest to save Princess Daisy. Nonetheless, most of them behave a lot like Bowser: they scuffle along a platform, or other kinds of scripted rails, while trying to stop Mario from reaching the other end.
All of them do have different models and unique animations, but they - except for a couple, one of which includes Tatanga himself - are fundamentally no more different than Bowser. Reaching the other end of the platform, or killing them with projectiles, simply causes them to explode (together with any sprites that they have generated, such as their own projectiles). This can be hardly satisfying, considering that the NES version had Bowser undergoing animations that suggest embarrassing defeats.
Much like the NES title, Mario's quest is foiled every time he tackled a region whose ruler is holding the Princess hostage - at least until he reaches the last region. However, it is no longer an aide of the Princess that tells Mario the disappointing news that the Princess is elsewhere, but instead, Mario has to encounter doppelgangers that dash his hope in a crueler manner.
However, to certain players, this may be a lot more amusing than an aid bearing bad news.
As for the overarching gameplay, Super Mario Land plays a lot like its NES predecessor: Mario runs from one end of a level to the other in a side-scrolling manner, while defeating enemies, collecting coins and chasing down power-ups that make his job easier.
It is worth noting here that the Flower power-up, which was known for changing Mario's looks and allowing him to throw Fireballs, had to be changed to accommodate the grayscale-only graphics of the GameBoy. The Flower does not change Mario's looks at all, which can be a bit disappointing and may impede gameplay if (for whatever reason) the player has forgotten that Mario had obtained the Flower power-up and there is no visual cue to remind him/her.
Yet, the gameplay changes that the Flower enacts do not merely amount to a palette swap. Instead of throwing Fireballs, Mario throws "Superballs", which do not skip along the ground but instead fly at 45-degree angles and can bounce off surfaces, without losing any height like the Fireballs of yore would. Furthermore, Superballs can collect coins too, something that Fireballs cannot.
Unfortunately, it appears that the Superballs are weaker, a fact that can be discovered upon using them against the generic enemies that are common across Mario games, such as Koopas. Moreover, Mario cannot rapidly launch Superballs like he could Fireballs.
Otherwise, the other power-ups in the game, namely the Mushroom and Starman, still work like they did in the NES title.
Like Coins in previous Marios, they can be collected for bonus points and cashed in for an extra life when up to a hundred had been collected. As in previous games, Coins have very obvious sprites, though they lack the flashing effects of those in the NES game. Fortunately, there would not be much confusion with other objects, none of which have any sprites that are similar to Coins.
A minor improvement to the scoring system here is that racking up a high score is no longer for just bragging rights; hitting every 100,000 points adds an extra "continue", thus extending the playing time longer for the moderately skilled player.
As mentioned earlier, every level ends with a jarring transition to a steel edifice with a blank background and two doorways at different heights. Mario can enter either to complete the current level, but entering the higher one is in the player's interest, as which door he entered will work into a tally of doorways that Mario has entered. To make reaching the higher doorway tougher, there are platforms that fall when he steps on them and, more often than not, the platforms needed to reach it are very narrow.
If the player can have Mario consistently entering the higher doorways, the tally will decide what kinds of rewards that the player gains when a region is completed. Obviously, a higher tally leads to better rewards, with extra lives dominating the top tier.
However, there are some amusing nuances to the reward system as well. Certain tiers are circumvented with upward-going ladders, which Mario will automatically climb to reach another, better reward, in an apparent cheating attempt. Of course, programming-wise, this only means that for some regions, certain rungs of tallies lead to the same rewards.
Nevertheless, this is a pleasant if somewhat visually unappealing change from jumping onto flagpoles and lowering flags.
Super Mario Land also features levels with vehicles. In these, Mario is not affected by any issue of gravity. Instead, he can scoot freely around the two axes of movement. He also gains a ranged attack with unlimited ammunition that he can spam. However, in return, the player has to contend with a constantly scrolling screen, with no way to accelerate the scrolling motion. Thus, these levels seem to be more like shoot-'em-ups than the platformer that Mario games are better known for. Nevertheless, the change of pace can be fun to some players.
Oddly enough, there is a timer for these levels of fixed scrolling speeds anyway. Most of whatever time that remains when the player reaches the end of such a level, which will always involve a boss fights, can be easily saved, due to how flimsily these boss fights are designed.
Bosses in these levels also have the freedom of movement in both axes, but they can only change positions along an unseen, scripted circuit. They also cannot turn around and will always spawn on the right edge of the screen when Mario approaches their sanctum. This meant that the player can exploit the vertical motion of Mario's vehicle to conveniently position him above or below the boss when it spawns, allowing the player to simply circumvent the boss fight altogether by bypassing them and reaching the lever or button that they guard (a la Bowser-style). As a consequence, fighting them can feel like a waste of time once these exploits are known.
Sound effects are typically those that can be expected from an 8-bit Mario game: beeps, boops, tinkles, warbles and other kinds of short 8-bit flourishes and onomatopoeia.
However, some of them can be annoying, especially the irritating droning noise that can be heard when the game counts the seconds that the player has left for bonus points when he/she completes a level.
The soundtracks in Super Mario Land are entirely different from those in the NES title. Most of them are original, with some being inspired by Mozart and a few other music luminaries. There are also a few soundtracks that pay tribute to other 8-bit games at the time, such as an Oriental soundtrack that is reminiscent of that in Yie-Ar Kung-Fu.
Regardless of the different themes of the soundtracks, they share a common trait, which is being upbeat. An especially good example is the soundtrack when the Starman power-up is gained.
Some soundtracks do repeat, such as the supposedly Egyptian-themed, high-bass soundtrack that is repeated for every subterranean level, regardless of the region currently being played.
In conclusion, Super Mario Land would at first glance, appear to be yet another Mario game, and its actual gameplay would not suggest otherwise. However, small but numerous shake-ups in gameplay designs ensure that the Super Mario Land series will be known for being different than the series for the consoles - and not just for being exclusive to Nintendo's handhelds either.