There are roughly twenty chapters and seven post-games (though I don't know what a post-game is). After the twenty chapters there are special missions to do (yay!)
Hope this helped
Source - My personal experience
If you're talking about Pokemon Mystery Dungeon Explorers of Time or Pokemon Mystery Dungeon Explorers of Darkness, you can recruit as many Pokemon as you want. If you are talking about Pokemon Mysatery Dungeon Blue Rescue Team or Pokemon Mystery Dungeon Red Rescue Team, you can only recruit a certain number of Pokemon per friend area.
There are 8 floors. Groudon awaits on this floor. Water or grass-type Pokemon are suggested.
I think it's just like Time or Darkness. If so, then it has 13 floors with no waypoint.
there are 83 shadow Pokemon in Pokemon xd: gail of darkness i know i have them all
83.
20 with 7 post ending chapters..veronica
2
Crystal Cave has 12 floors in Pokemon Mystery Dungeon: Explorers of Darkness.
19 and a summit
16
157 :)
12
The Temporal Tower has 23 floors in "Pokémon Mystery Dungeon Explorers of Darkness."
There is 20
48 floors
19. ~PikiSkymin.
20 floors