"Gargoyle's Quest", Game Boy, 1990

Not a lot to say here, except that it may be the only occasion upon which the Game Boy has been accused of having graphics that are "so real". A world where the Game Boy's greatest graphics were the pinnacle of reality would be an Orwellian nightmare where everything was chunky and tinted Soylent Green.

GRAPHICS SO REAL YOU'LL FORGET IT'S ONLY A GAME

Dazzling graphics and excellent sound bring a whole new dimension to the Game Boy! Enchantment and excitement await you in Gargoyle's Quest.

Prepare to do battle as Firebrand, the last Guardian Gargoyle of the Ghoul Realm. You must act quickly to defend your world against an invading army of Destroyers.
Fight your way through enemy forces to reach the dimensional portal that leads to your home world. Once there, the true nature of the quest begins.
The King of the Ghoul Realm has been kidnapped and it's up to you to save him. Blast the attackers with fiery breath as you fly through their defenses. Unravel the mysteries of this multilevel universe to succeed in conquering the Destroyers and freeing the captive King.

• Highly-detailed artwork sets new standards for the Game Boy!
• Advanced playability, highlighted with 360 degree scrolling.
• Hours of entertainment await you in this diverse adventure.

Others have written (hm, quite recently!) on the other relative merits of the game, relatively untouched-upon by this breathless advertising copy. It was certainly interesting as an early demonstration of the "last game's villain is this game's hero" trope (not to the extent where the baddies are human knights, though), recalling protagonist Firebrand's prior appearance in Ghosts 'n Goblins -- where his skin was red, not green. Many bored bloggers have wasted many keystrokes bemoaning how this game's cover artist had clearly never played the G'n'G games and hence had no idea what colour our hero's skin was supposed to be. But surely he played the heck out of it on the GB, where everything was tinted pea-soup green!
Three closing remarks: first, that the game-player's right hand in this ad does look more than a little wonky, and second, that the cover art (better view here) appears to suggest that the greatest (or surely at least most satisfying to deploy) weapon in Firebrand's arsenal was in fact hidden beneath his loin cloth. Look at the way that pink triangle thing is visibly recoiling! (The horned crab-toad, conversely, appears intrigued, as though it wants to get a closer look.) Finally, have you heard my story about the origin of the word "gargoyle"?