The Nintendo Game Boy conversion of Bubble Bobble is not an authentic port of the arcade game, even though it was developed by Taito themselves.
The levels are different to those seen in the original and the screen scrolls as Bub moves around. There are some similarities to the original levels, but in general they’re mostly different. There are also some unique cut scenes, but they don’t add a great deal to the game itself.
Not being able to see much of the screen at the same time is a problem – it’s far too easy to run into enemies that you can’t see, or drop down a hole into a bunch of enemies below that you couldn’t see.
One of the biggest issues I have with this game – other than the small play area – is that a lot of the sprites strobe in halves, so half don’t show up properly in screenshots (which is a problem for me – I had to recreate bubbles that were split in half in the screenshots below).
Other differences to the original? There are new boss battles. Ghosts now shoot what look like miniature planet Saturns, instead of fireballs, which seems kind of arbitrary. Space Invaders make an appearance, and they even shoot bullets downwards (like in the classic Taito arcade game), and my guess is that other Taito characters make guest appearances, but to be honest I didn’t get that far into to the game to find out. The game is also single-player only – there’s no two-player link option.
I didn’t like this conversion very much. The strobing sprites gave me a headache and I got tired of running into enemies that I couldn’t see. The jump inertia is weird too. The Game Boy deserves better, to be honest. Taito probably felt the same since they followed this up on the Game Boy with the much better Bubble Bobble Part 2 in 1993.
See also: 10 Best Bubble Bobble Conversions