Inspired by St0rmychu on discord: 
Which lead to the discussion of the possibility of raid bosses in PMU, especially with upcoming Pokemon Sword and Shield with Raid bosses, and Gigamaxing.
Raid bosses not an unfamiliar mechanic with neither MMOs, the pokemon franchise, or pokemon mystery dungeon sub-franchise of games, and I could see adding raid bosses to PMU to be a very interesting concept, in terms of motivations and rewards, and I am very interested in hearing your thoughts on the matter, let me dive in to how I could picture some of the mechanics functioning
What would raids be?
I’d like to steal another one or two things from St0rmychu, as they are essential parts of how this will function.
Players will enter a room with a boss pokemon, in a party size of double the standard and continue to beat up a buffed boss.
Where would they be? and What type of raids would there be?
I could potentially see 3 or 4 difficulties of said bosses ranging from, easy, medium, hard, ex, and almost a combination of raids from gates, sword and shield, and pokemon go. The way of accessibility would be up to staff, but I could see them ranging from outsides dungeons, to midpoints (Bring back flying Pikachu as a raid boss in SF Midpoint for example?), to ends, to scattered randomly over the many regions.
What would I need to enter raids?
I could potentially see a limit, probably weekly, similar to pokemon go except linked to explorer rank, perhaps require keys to enter raids, keys that are given out weekly and used similarly to passes, except limited to the difficulty they are obtained specifically for, also thus limiting new players specifically towards raids their level. For example
Bronze: 1 Easy key
Diamond: 2 Easy key 1 Medium key
Hyper : 3 Easy key 2 Medium key 1 Hard key
Guildmaster: 4 Easy key 3 medium key 2 hard key 1 Ex key
Purely theoretically, perhaps raids themselves could even offer explorer points and help with the progression? moving on to my next suggestions.
What could be the rewards for raids?
I was thinking possibly for lower tiers, maybe pokemon that are simply difficult to find? (Like Goomy, Beldum, ect, and once again just an idea, feel free to suggest something better.) That the raids will spawn 100% of the time (But not a 100% recruit rate keep that in mind, to motivate people to continually run low difficulty raids.)
Each player after defeating the boss being separating from the group, and entering a room containing at each respective difficulty.
Easy: Rare Stage 1 recruit that evolves (Goomy, Beldum, Alolan Meowth)
Medium: Medium rare item, decent poke item, or rare stage 1 recruit that doesn’t evolve (Smearagle, Heatmor, Zangoose)
Hard: Rare item, upper-tier relic, maybe Gem/Crystal, or event tokens.
Ex: Now this mode in it of itself is entirely super theoretical, and the way I see it could be a great way to introduce legendaries, ultra-beasts, and their respective family items, in the reward rooms, is a Box, inside the box could contain either a key (Or pieces to a key? up to you guys, which combined with the mp and heart slate could maybe be used to recruit said legendary?) or potentially a family item for said legendary defeated.
Now besides from physical rewards, this would also provide motivation for players to train pokemon that fill multiple roles, and type match-ups, that is why raids in MMOs, are important so important in general, they prevent, or at least attempt to prevent the over-saturation of the damage class or classes. Come on guys, make playing a tank in pmu more rewarding?
How hard would/should raids be?
Well, I really should have put this earlier especially before rewards.
Restriction are a possibility to keep things balances, for example, no one above level 40 in easy raids, etc, and you get the idea, to keep things interesting, and for players to require a party at the max or somewhat near it. As for the break up, I am thinking something similar to the way pokemon go breaks up their raids, but on a smaller scale, compressed scale, something like, easy being stage ones lvl10-40 medium stage twos lvl30-80 hard stage threes lvl80-100 ex legendaries, Ultra beasts, (Megas and gigamaxes later maybe?) lvl100.
Once again, all only theoretical and suggestions, please say whatever you think is better I want to hear your opinions, this is just a starting point.