These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Bubble Bobble
Even the Bubble Bobble games can be very confusing, self-changing, or imperfect.
Porting Disaster: Let's just say that most of the non-arcade versions were not well received. The port-bashing section of the first game's Wikipedia article vastly outsized anything else for a while.
Incineration deaths in the arcade are only otherwise seen in ports on any of the Game Boys and the DS, and although the original GB version kept the style of the arcade sprites during incineration, over half its frames are cut out resulting in a quicker and choppy animation. The GBC version "Classic Bubble Bobble", which generally took the character sprites from Part 2/Junior, uses a wholly different and jarring incineration animation.
The squish-yourself-against-bubbles animations are implemented (fully but poorly) only in the Game Boy Advance and DS ports of the original.
In the GBA/DS ports, deaths did not match the arcade implementations. In the port, you freeze in midair when you start spinning out instead of just before you poof away into magic dust. Also, the standing-non-dead sprite frame is used, followed by the sitting-down-dead sprite frame only when your character spins out.
For the Wii and Xbox 360, they've been replaced (or chronologically preceded?) with two other females named Pab and Peb (according to the Title Operations Guide on the Wii Shop Channel), supposedly Bub and Bob's girlfriends (This causes a Series Continuity Error, as if the series had any plot sense beforehand; the girlfriends in the first game were stated as Betty and Patty.)
For the DS, we have Robolun and Lovelun (a just-as-defenseless robot, and a pink unknown-gender bubble dragon, respectively), and a cousin (red male bubble dragon) named Bubu.
Shocking Swerve: True ending of the arcade version, which was ported to the NES and thus the Virtual Console. Then the GBA and DS. And other faithful arcade ports.
Level 99 is also guaranteed to cause some headaches!
The Level 99 in the NES/VC version is even worse. Players are suddenly required to get a crystal ball so they can go through a secret path and get a good ending. And items will disappear after a while.
And Level 35 is pretty much the end of the game to anybody who can't figure out the bubble jump mechanic, or are not aware of the arcade's Attract Mode in which it shows how to do the bubble jump, making this a Gimmick Level. It doesn't help that this jump is made even harder in the C64 version.
Woolseyism: Bubble Bobble's NES manual and Puzzle Bobble/Bust-A-Move's SNES port rely on such names as Bubble Buster for the iconic wind-up toy Zen-chan, Stoner for Mighta, Super Socket for the Invader, Willy Whistle for Drunk, etc. Puzzle Bobble gave the secret room Invincible Minor Minion Rascal the name Rubblen. But then Bubble Bobble Part 2's NES manual gives them wholly different names.
Self-contradictory in the NES/Virtual Console version of the first game in that if one beats the game with the best ending, a screen with both protagonists and all enemies show up credited with their original names.
Although Bub and Bob's short 3-letter names have been products of Woolseyism, they work better.