8.8: The fans were not happy about some review scores, particularly the 3/10 Game Informer gave Blue Rescue Team.
Of particular note is IGN's 4.9 rating of Explorers of Sky, even lower than their score of Explorers of Time/Darkness. It's certainly not helped by Explorers of Sky being seen as the best installment in the series by many PMD fans.
Annoying Video Game Helper: AI teammates often embrace this trope with both hands, especially with low IQ stats. Reviving an entire room of petrified enemies with an ill-timed Growl attack, for example.
Epileptic Trees: The Decrepit Lab is solid evidence that there used to be humans in the world where Red/Blue Rescue Team takes place. The unanswered question is... what happened to them? Theories include:
Human civilization suffered an extinctionary catastrophe thousands of years ago and the story of Red/Blue Rescue Team takes place in an "After Humanity" era where Pokemon have become capable of intelligent speech.
Humans have permanently departed from the planet in a massive Space Exodus, leaving behind their infrastructure as the only evidence of their former presence.
Humans still exist in the world but the location that the story of Red/Blue Rescue Team takes place is largely unknown and inaccessible to them. The Decrepit Lab is possibly evidence to a failed attempt at colonization or just a remote research station that met with disaster.
Since Mewtwo was created by humans, he might be the only Pokemon in the series who has some knowledge and history about them. But it remains an unexplored plot hole since no one bothers to ask and he never says anything about it.
Fake Difficulty: Since the beginning of the series, in some later dungeons, it's possible to run into Monster Houses, which house tons of very powerful enemies that are hard to dispatch without being killed. Overcoming one wastes a lot of resources. You're probably better off resetting if you encounter one, because it's ridiculously frustrating to take on and not fun.
Unlike the main Pokémon series, "movement speed" actually provides a Haste effect, giving the user multiple turns in a row. It wears off quickly, but a quickened Pokémon can inflict a lot of damage if they also know attacks capable of hitting an entire room. This goes double in Monster Houses, where an enemy Pokémon using "Agility" can increase all enemies to double/triple/quadruple turns.
Multi-Hit attacks (Bullet Seed, Fury Swipes/Attack, Pin Missile). Due to the damage calculation in the Mystery Dungeon games being much different than the mainstream titles, these moves now hit as hard as most other attacks each individual hit. This is made worse for the fact that the STAB bonus from the mainstream titles is also implemented in the Mystery Dungeon games, meaning with the right Pokémon (A Treecko with Bullet Seed and the Concentrator skill for instance), this can be quite lethal.
Petrify or Foe-Seal Orbs render Monster Houses pretty much trivial: they freeze every enemy in the room until attacked, letting you mop them up one by one and gather the sweet loot. What's more, your A.I. team is smart enough not to attack any enemy under the effect, so you don't have to worry about them ruining it and dooming you.
Pretty much anything that can inflict Poison status, attack from a distance (most Water-type attacks have ranged capability), or from within walls (the Ghost types).
Doom Seeds: You better pray that an enemy 'mon doesn't throw these at you...
Spinarak, a mon that can cause the aforementioned poison along with a slow, causing it to go twice as much as you.
Hilarious in Hindsight: The Koffing-Skuntank-Zubat trio from Explorers is referred to as Team Skull, a name that would later be used for the street gang from Pokémon Sun and Moon. Gladion, who serves as the enforcer for Sun and Moon's Team Skull, has a battle theme whose beginning sounds extremely similar to that of "Runaway, Fugitives" from Rescue Team.
Nintendo Hard: Especially the bonus dungeons, some of which totally empty your inventory and level you down to 1. It's because of this that Purity Forest and Zero Isle South are many players' favorite dungeons.
Popular with Furries: While the Pokemon already has a good following in the furry fandom, this series receives heavy attention from it due to the Pokemon being the viewpoint characters rather than the humans.
Signature Scene: The ending of Explorers where the hero has to leave is widely considered the saddest moment in the whole series by many fans. It's not really different from the ending to Rescue Team, however, but it seems to be far more popular.
Gates to Infinity has also been hit with this since the Japanese demo was first released. For details, see its entry below.
Tier-Induced Scrappy: Pretty much anyEscort Mission you do will include this. You can't assign tactics to them if they get separated, and in Red/Blue Rescue Team the escorted Pokémon was almost always at Level 1, making it easy for enemy Pokémon to KO them. To put it nicely, these are the guys who tend to waste all your Heal Seeds and Reviver Seeds for doing annoyingly stupid things like wandering off and walking into lava/fire. Explorers was just a little bit nicer in the levels department, but your clients are still under-leveled.
Tough Act to Follow: Gates to Infinity is having a very hard time following the Explorers games, mostly for "not having a deep enough plot", and the fact that there is a lot less post-credits content compared to the other two games.
Regarding this trope in general, some fans feel that Mystery Dungeon spinoff series tried too hard to be Darker and Edgier without adding aspects of explicit violence, swear words and other adult things in order to appeal to young players.