What a coincidence; I'm also currently working on an essay on symbolism for a different game. Here's an excerpt:
"As the player advances in levels, they get to watch our plump crimson plumber descend further and further into his own psychoses. Enemies assault him with greater veracity and in greater numbers, the pits and perils he must face widen and dot with increasing frequency the pockmarked landscape, and power-ups - the "magic" mushrooms and flora that maintain Mario's delusion - become rarer still, such that the discovery of one marks a momentous occasion for both character and player. These new challenges betray a growing desperation. As the princess continues to elude our hero's grasp, he finds it harder and harder to move on; thus, the manifestations of his delusions become wards against his pressing on, as if to say, 'turn back, or all will be lost: not only the princess, but you as well!'
"Now, I have spoken before concerning the various power-ups our hero uses and how they reflect his changing mental state; therefore, I will reiterate them briefly. In his neutral state, Mario finds himself small, only one bare scratch away from death. In every sense, in this state, he is powerless against the world around him, save for the ability to jump upon his enemies (hardly an effective offense in the hostile Mushroom Kingdom). The mushroom, however, grants the illusion of "bigness" and strength; with it, our hero not only believes himself to be greater than he truly is, but it also numbs him from the pain of bashing his fist against blocks, allowing him to shatter them with a mighty blow. The mushroom may therefore be analogous to PCP or a similar dissociative in the "real world." Similarly, the "fire" flower acts as a hallucinogen, combining with the numbing effects of the mushroom to allow our hero to imagine that he can smite his demons with balls of pure flame. Finally, the "star," of which there is no equivalent in our reality, may very well be purely imagined: a device through which our hero copes with his ugly reality by imagining himself a Superman-type figure for a short time.
"These 'power-ups' not only grant Mario himself power, but also allow his player to experience Mario's rush of adrenalin firsthand. Who, for example, did not feel a surge of sheer power when they first obtained a star from a question block, allowing them to plow their diminutive hero straight into hordes of marauding assailants? In that sense, the almost complete removal of 'power-ups' from the later stages of the game gives the player an increasing sense of powerlessness, a feeling equaled only by the sad, tiny figure of 'small' Mario as he wanders along his chosen path, trying desperately to stay alive as he inches toward the love of his life, the Princess, without whom his life is but a psychedelic dream, a fleeting series of images and encounters, signifying naught except what lies within his substance-addled mind."
(...I feel several IQ points stupider after writing that.)
