The genesis of Metroid is relatively well known and takes place at the time when the Famicom saw an increase in storage capacity for games. Two directions were taken: the first is well known, it is The Legend of Zelda (1986), with the Dream Team in charge of the project – Miyamoto, Tezuka, Nakago, to name but only a few. A few months after, Metroid was also intended to be a non-linear title in its progression, but for the action-platformer genre. The team was different, as it was led by Satoru Okada and Yoshio Sakamoto, who had won their spurs on ports of arcade titles.

The scenario is more elaborate than the majority of the titles of the time and is backed with an extensive lore in the manual: we play as Samus Aran, who has to find the Metroids, stolen by the space pirates. These are holed up on the planet Zebes, which serves as the main exploration site. If the influence of The Legend of Zelda, in the non-linear construction of the world and the quest for objects to facilitate exploration, is obvious, Metroid innovates by its claustrophobic aspect. The cramped environments force anxiety, which the music often compliments. Brinstar, as the first locale, has heroic flights in its melody, while the bass in Kraid's Hideout creates anxiety with throbbing arpeggios and an ostinato that mimics a heartbeat. The soundtrack clearly plays on this carnal side, especially in Ridley's Hideout or in the secret rooms: strangeness is invited by chaos or silence, which take hold of the throat. The influence of Alien (1979) is undeniable and documented.

It is this mysterious, almost frightening side that accompanies the exploration of Zebes. Our initial, very limited arsenal prevents us from moving around as we please. The initial inability to attack ground-crawling enemies makes some sequences more complex than they seem, and it stays a perennial problem. Missiles are an effective expedient against more powerful enemies, but their number is limited, pushing a conservative approach when using them. Only the Screw Attack sets us free, but this is well hidden in a corner of Norfair. For the majority of the game, exploration thus remains a breathless challenge. This exploration, while intended to be organic, can nevertheless be broken down into several sequences – more or less interchangeable. From Brinstar, three zones radiate out and allow us to acquire upgrades. It is possible to explore Brinstar and then Kraid's Hideout; then Norfair and Ridley's Hideout, before tackling Tourian. This last area is the only one that is conditional on exploring other areas, as it is pegged to the death of Kraid and Ridley. Otherwise, it is possible to explore freely, although some passages require a certain amount of creative skill to progress without key items (Ice Beam, High Boots). We can already see the emerging potential of Metroid in this opus, especially the bomb jumping – though it's a bit different from the way it is done in Super Metroid, in that the game sometimes doesn't recognise the B button imput, when you want to drop a bomb in the air.

Beyond these qualities, Metroid is still a NES game and is limited by the technology of its time. Interviews have pointed out that storage was at a premium, so assets had to be reused to compress the size of the game. In practice, this results in rooms that are sometimes very similar, if not absolutely identical. Unfortunately, this makes exploration less iconic and, much more so than in Super Metroid, it seems essential to rely on an external map, as it is very easy to confuse one corridor with another. The lack of eight-way directional shooting feels limiting, especially as Samus can't redirect her gun in the air, leaving her sometimes defenceless against some fast-moving enemies. The game also lacks a bit of visual cueing to guide us through its world. Tourian requires possession of the Ice Beam to freeze the Metroids, but the title is never really clear on this point – admittedly, it places one in Norfair, in a more or less convenient location after facing Ridley, but this is somewhat inelegant. Similarly, some of the secret passages are viciously hidden and require, similar to The Legend of Zelda, the player to bomb every block to ensure it's not crumbly – the situation is even worse with the fake lava lakes. These little hiccups can detract from the quality of the exploration, especially as the difficulty remains generally high.

A quick word on the representation of gender: depending on the speed at which the game is completed, the ending screen may reveal that Samus is a woman; exceptional speed even shows her in a bikini. The inspiration is again Alien, with Ripley. Nevertheless, it is obvious that this choice is still situated in a very sexist environment, to the point where a non-negligible part of the public did not admit that Samus was a woman – Western magazines not helping on this point, notably because of the confusion surrounding the password 'JUSTIN BAILEY'. Fatally, the subversive side of Samus eroded quickly – perhaps less so for the manga? This is illustrated by her sexualisation in Zero Suit Samus, as well as in the themes of Metroid: Other M (2010). In any case, Metroid remains an essential game, even if it has not aged very well and Zero Mission (2004) is far more easily recommended.