Scoring was based on three kinds of points: Skill (when the player performs deeds that help him in his quest, or defeats enemies), Wisdom (when examining things, talking to others, or gaining hints) and Soul (performing good deeds to help others). The options provided a difficulty setting for the arcade sequences, but with lower points. The game featured a soundtrack of authentic-sounding medieval music composed by Mark Seibert.
The package included a map of Europe in Arthurian times and an illustrated manual called Liber Ex Doctrina (a Latin pun, for while it can be read "book (derived) from knowledge"—i.e. the game documentation—it can also be read "free from doctrine"). This book included information about the evolution of the Arthurian and Grail myths as well as Greek and Roman mythology; some of this information was required in order to answer riddles within the game.
The adventure itself concerns Camelot only briefly. The player travels across England in order to fight with the Black Knight and rescue Gawain. Then the ruins of Glastonbury Tor where a mad monk claims he has the Grail, left by Joseph of Arimathea; the player can also see the Glastobury Thorn and open a well, the lid of which curiously resembles the Chalice Well. Afterwards, he visits Ot Moor where the frozen (due to the curse) Lady of the Lake challenges Arthur to a riddle in order to rescue the imprisoned Lancelot.
Arthur then leaves England in order to follow Galahad's traces. He arrives to Gaza (where he will be hosted by a man called Al Sirat, who will introduce him to the cult of the Six Goddesses) and reach Jerusalem. Arthur will be tried throughout his journey in Palestine, and acts of selflessness and helping people will add to his Soul point system.
The player is given a choice in how to proceed through the game: for example, the player may decide not to fight the Black Knight, but must face the consequences of those decisions.
The I of the official title, as well as the epilogue, indicated a sequel – probably Conquests of Camelot II – but instead Marx proceeded to Conquests of the Longbow.
The narration makes a preference to less known forms of words, for example Gwenhyver, Excaliber, Gawaine, Launcelot, magick instead of the better known Guinevere, Excalibur, Gawain, Lancelot, magic. The parser however will understand all alternative forms without a problem.
Conquests of Camelot is heavily colored by its heavy religious overtones, since the game is centered around the recovery of the Holy Grail. If appropriate tributes are not made to Christ and Mithras in the beginning of the game, Arthur will never venture beyond the walls of Camelot, as the castle's grating will fall and kill him. If Arthur decides not to help his knights, avoid thus the trials and arcade sequences, the Grail will also kill him at the very end of the game.
The Grail's power seems to be universal both as a Christian relic and an artifact (the cauldron) of feminine power of the Goddess in pagan folklore. The old gods, such as Mithras, Cernunnos and later Aphrodite are portrayed as real gods, but their powers and influence are in decline because of the advent of Christianity. In the ending sequence of the game, the Grail obliterates Mithras' symbol in the chapel.
However there are no religious authorities such as priests that are encountered in the game; the Mad Monk is revealed as serving the "Old Ones". If the player specifically asks Merlin about Rome, he will comment on the Bishop of Rome and the Church, but this is the only mention of religious authority. However when the player moves the cursor around the map of England, Merlin will frequently comment on early legendary Anglo-Saxon saints. It must be noted that in Longbow all monks and religious figures (besides Friar Tuck) are villains.