''Conquest of the Crystal Palace'' (original Japanese title: ''Matendouji'') is a side-scrolling PlatformGame released on the UsefulNotes/NintendoEntertainmentSystem in 1990.

The realm of the Crystal Palace was once a thriving kingdom, until the evil war spirit Zaras came and started wreaking havoc, causing the inhabitants of the palace to run for their lives. One young swordsman, Farron, comes forward along with his faithful guardian dog Zap in order to defeat the demon and restore peace to the kingdom.

The game has five levels where Farron will jump, hack and slash his way through enemies and encounter bosses. From time to time, he can purchase items from a shopkeeper named Kim, who will also brief him on the current situation around the Crystal Palace, if he so asks.
!!This game uses the following tropes:
* [[ABoyAndHisX A Boy, His Sword and His Dog]]
* AnimeChineseGirl: Kim, complete with tying her hair in buns.
* BlowYouAway: Kergen, the second boss, will occasionally blow you toward the edge of the screen.
* CanineCompanion: Zap
* DescendingCeiling: The path leading to Zaras has a spiked ceiling that quickly drops on Farron. If he doesn't open the door fast enough, the spikes will crush him and you'll lose a life.
* DualBoss: Kentar and Kellix, the first bosses.
* FastballSpecial: If you use the Dog Whistle while Zap is on the screen, you can launch him into enemies at high speed.
* FlunkyBoss: The third stage boss.
* {{Meganekko}}: Kim, when newsreading and when explaining how the special weapons work.
* NonLethalBottomlessPits: The two castle stages (the second and fifth) have them. Instead of dying, you get bumped back to the last (invisible) checkpoint you passed.
* PrecisionGuidedBoomerang: The Boomerang Annihilator magic weapon has short range, but will eventually return to Farron no matter where he is on the screen. With clever jumping, he can make the bullet orbit around him (à la Ryu from the NES ''VideoGame/NinjaGaiden'' games).
* SaveThePrincess: An optional challenge, but if you do complete it, you'll get the powerful Moon Mirror, which destroys weak enemies instantly.
* SmartBomb: The Moon Mirror.
* VictoryPose: Farron does a dance and flashes a VSign after defeating a boss. If Zap is alive when you win, he runs around you for a few seconds before doing the same thing.
* VideoGameCrueltyPunishment: If you try to buy an item several times when you don't have enough money for it, Kim gets angry and throws you out of the shop.
* WombLevel: The third level, the Lair of Hungry Ghosts.