I can't think of the last time I encountered a game-breaking bug, but my playthrough of Final Fantasy Adventure on Game Boy was tragically cut short about halfway through due to a bug where you can get stuck in a dungeon in between two locked doors and no key drops or item shops anywhere to be seen. This was really too bad, because up to that point I'd been enjoying this first entry in the Mana series, and it had been a while since I'd finished an OG Game Boy game. But it was not to be.
Final Fantasy Adventure has similar gameplay to the top-down Zelda games, and what it lacks in refinement and character it makes up for with some novel game mechanics. The path is pretty linear and you steadily accrue more powerful weapons and armor. Specific weapons are needed to progress past certain obstacles (for example, an axe can cut down certain trees, which open up new pathways). Switching between them is somewhat of a chore, but to be expected given the Game Boy's limited controls. Oftentimes you'll have a companion keeping you company on your adventure, and companions have unique skills, such as being able to restore your health. You accrue experience points as you defeat enemies, and there's a basic progression where you can choose how to allocate your skill points to various categories (magic vs. strength vs. defense, etc.). Nothing too earth-shattering, but novel enough for the time. The save anywhere feature is a great boon, especially given that the game is on Game Boy, but proves to be the game's downfall as it can lead to being trapped as happened to me.
The game isn't related to the mainline Final Fantasy series much at all, and shares its name no doubt simply to capitalize on that series' success (Final Fantasy Legend, which preceded it by a couple of years, included the Final Fantasy name only in its English release, but FF Adventure included Final Fantasy in both its Japanese and English names). In any case, although the game is very basic by today's standards, it includes a variety of enemies, locales, items, and spells, and a plot that throws the occasional curve ball. The inventory is far too small and you'll end up spending a lot of time going into your menu in order to throw away items, but aside from the game-breaking bug overall this was a pretty decent little early action RPG. I'm disappointed I wasn't able to finish it, but I'm probably going to go on and check out its sequel, the highly regarded Secret of Mana on SNES, rather than retread hours of this game.