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.
Game Breaker: Certain characters had "impale" attacks with their weapons which would constantly sap life from the opponent until they keeled over. Granted, these attacks could be blocked, but there's a reason they never resurfaced in Deception and Armageddon.
John Vogel: We were fully prepared to say "Yes, [Jax killing him] really happened. He's dead. He's gone." But Mortal Kombat Armageddon is about bringing every character back to life, so Hsu Hao is back... much to my dismay.
Drahmin, although not to the extent of Hsu Hao, also earns a similar reaction from the fans. Ed Boon notes that he's one of his two least favorite characters (the other being Hsu Hao), and he's unpopular with fans due to how newcomer-unfriendly his playstyle is. The flies swarming him and constantly buzzing was a rather distracting nuisance.