Knights of Xentar is a sequel to Dragon Knight II, and is the only Dragon Knight game that was released outside of Japan.
The player controls a young warrior named Desmond (Takeru in the Japanese version). After liberating Strawberry Fields from an evil curse in his previous adventure, Desmond finds himself in a situation unworthy of his heroic status: robbers have taken all his possessions, including his magic sword, and even his clothes! So the first task for the unsuccessful hero will be to get some money. Luckily, the mayor has an assignment for the hero, for which he is also willing to pay. Desmond accepts the assignment without knowing what it will lead to - traveling all over the world, fighting fearsome enemies, encounter beautiful women, and solving a mystery that will also reveal the secret of his own true identity.
The game is a humorous RPG with erotic content. The gameplay is quite different from that of the previous game. The player travels in top-down view on the world map, visiting towns and dungeons, like in most traditional Japanese RPGs. Enemy encounters are random. Battle system differs from most other games of its type by being real-time: combatants appear on a side-scrolling area and exchange attacks automatically; the player can interfere at any time and issue orders to the characters in the party - cast a spell, use an item, or change the attack power level. Physical attacks have a gauge with eight different power levels; the higher the level is, the stronger is the attack, and the slower is its speed.
Knights of Xentar features anime-style cutscenes, many of which contain erotic images - the girls Desmond encounters and helps will often feel grateful and award him with some "treatment".
Near the end, one of the creatures you encounter is a "Tetsuo". This misshapen baby-like blob is taken directly from the anime Akira.
Knights of Xentar is actually part of the Dragon Knight series. For some reason Megatech couldn't get the rights to distribute the game with its original name so they had to change it for legal reasons (a common happening in the world of animé/manga translations), Megatech included their legal woes in the game however, and you can read all about it in the Hentai scene with the princess where she starts blabbling about how sad it is when legal crap gets in the way of good entertainment.
The English translation is supposed to be quite unfaithful to the original and the NR-13 rated version was created by Megatech by editing some pictures and removing some stuff. The only Japanese version is the full NR-18 release.