Before we go over what the names mean, let's cover a few important things. Dragon Quest 9 only recognises maps by two specific things: Quality and a random seed. Quality is a number between 2 and 248 that determines how good a map might be, and the random seed gives one of 32768 maps of that quality. So that means there are over 8 million maps in the entire game. So far, so good.
The quality of a new map is based on the hero's level and the level of the grotto you just completed. The basic formula is in fact as follows:
New Quality = Hero's Maximum Vocation Level + 5*Hero's Maximum Revocation + Level of Previous Grotto
Only the hero's levels count (the rest of your party doesn't), and only your maximum levels/revocation count. So if you're currently an L1 Luminary, but you have L50 in Minstrel, then you count as an L50 character. And if you've used revocation on your Warrior class twice, but your Gladiator class three times, then you count as having used revocation only three times for the purposes of grottos. Note that you can only use revocation on a single class a maximum of 10 times.
And no, getting yourself killed will not increase the quality. It's revocation only.
This quality can also vary by up to 10% in either direction, so a base quality of 100 could actually be anywhere between 90 and 110. And as stated previously, Quality is capped at 2 minimum to 248 maximum.
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Once we have a Quality for the map, the three primary stats of the map can be generated via the random seed. These are how deep the map is, how strong the monsters on the first floor are, and what boss lurks at the bottom. They are randomly determined based on the quality:
Quality 2- 55: 2-4 Floors, Rank 1-3 Monsters, Boss #1-#3
Quality 56- 60: 4-6 Floors, Rank 2-4 Monsters, Boss #1-#3
Quality 61- 75: 4-6 Floors, Rank 2-4 Monsters, Boss #2-#5
Quality 76- 80: 6-10 Floors, Rank 3-5 Monsters, Boss #2-#5
Quality 81-100: 6-10 Floors, Rank 3-5 Monsters, Boss #3-#7
Quality 101-120: 8-12 Floors, Rank 4-6 Monsters, Boss #4-#7
Quality 121-140: 10-14 Floors, Rank 4-6 Monsters, Boss #5-#9
Quality 141-160: 10-16 Floors, Rank 5-7 Monsters, Boss #6-#9
Quality 161-180: 10-16 Floors, Rank 5-7 Monsters, Boss #7-#10
Quality 181-200: 11-16 Floors, Rank 6-9 Monsters, Boss #8-#12
Quality 201-220: 12-16 Floors, Rank 8-9 Monsters, Boss #1-#12
Quality 221-248: 14-16 Floors, Rank 9 Monsters, Boss #1-#12
Note that the listed number of floors does not include the boss floor, and that for every 4 floors you descend, the Monster Rank increases by 1. So in order to face Rank 12 Monsters, you need a Grotto that starts at Rank 9 monsters and is at least 13 floors deep.
Also, you won't get better maps unless you cross over into the next quality bracket, so you don't need to feel you have to push yourself through the absolute highest level map you have if a slightly easier one would reach into the same bracket.
The game gives you four bits of information about a map to help you figure out what it's like before you enter. These are its Level, Prefix Name, Suffix Name and Environment Name.
Level: A map with 2 Floors (not including boss floor), Rank 1 Monsters on 1F and Boss #1 (Equinox) has a base level of 0. For every extra Floor, increased Monster Rank or increased Boss Rank, an extra 3 levels is added. Finally, a random number from -5 to 5 is added to the level. This means that a map with 10 Floors, Rank 4 Monsters and Boss #7 (Atlas) would be Level 46 to 56.
Prefix: The prefix gives an indication of how strong the regular monsters in the grotto are. This is randomly assigned, so each prefix could be a number of different monster ranks. This is also used to help determine what will be in the treasure chests you find, so it can be pretty important. The prefixes are as follows:
Clay..............Monster Rank 1-2
Rock.............Monster Rank 1-2
Granite.........Monster Rank 1-2
Basalt..........Monster Rank 1-4
Graphite......Monster Rank 1-4
Iron...............Monster Rank 3-4
Copper........Monster Rank 3-8
Bronze.........Monster Rank 3-8
Steel............Monster Rank 5-8
Silver...........Monster Rank 5-8
Gold.............Monster Rank 5-8
Platinum.....Monster Rank 5-9
Ruby............Monster Rank 7-9
Emerald......Monster Rank 7-9
Sapphire.....Monster Rank 7-9
Diamond.....Monster Rank 7-9
Suffix: The suffix gives an indication of which boss awaits you at the bottom. However, since each adjective can cover a number of different bosses, it can only be used as a very rough guide: it's easier to just use the Quality data to determine what boss you should be getting. The suffixes are as follows:
Joy, Bliss, Glee...................Bosses #1-#3
Doubt, Woe, Dolour............Bosses #1-#6
Regret, Bane, Fear.............Bosses #4-#9
Dread, Hurt, Gloom............Bosses #7-#12
Doom, Evil, Ruin, Death....Bosses #10-#12
Environment: The final piece of information is the actual place name. This has two pieces of information to be gleaned: how deep the grotto is, and what type of landscape you'll find inside the grotto. There are 5 different environs: Caves, Ruins, Ice, Water and Fire. Each environ have their own monsters. The environ names are split into 8 ranks, which are as follows:
Rank 1 Environs (2-7 Floors): Tunnel (ruins), Cave (everything else)
Rank 2 Environs (2-11 Floors): Crevasse (ice), Marshe (water), Mine (everything else)
Rank 3 Environs (4-13 Floors): Icepit (ice), Lake (water), Crater (fire), Lair (everything else)
Rank 4 Environs (6-15 Floors): Snowhall (ice), Moor (water), Dungeon (fire), Path (everything else)
Rank 5 Environs (8-15 Floors): Crypt (all environs)
Rank 6 Environs (10-16 Floors): Ruins (ruins), Tundra (ice), Waterway (water), Nest (everything else)
Rank 7 Environs (12-16 Floors): World (all environs)
Rank 8 Environs (14-16 Floors): Abyss (cave), Maze (ruins), Glacier (ice), Chasm (water), Void (fire)
Grotto Chests
With the exception of the first two floors of a Grotto, every floor will have between 1 and 3 blue chests. The number of chests found is completely random and based only on the map's random seed: nothing else affects it.
Each chest will have a set rank which is based off the Monster Rank of the floor you find the chest on. The range of ranks a chest may have are as follows:
Monster Rank 1: Chest Rank 1 to 2
Monster Rank 2: Chest Rank 1 to 2
Monster Rank 3: Chest Rank 1 to 3
Monster Rank 4: Chest Rank 1 to 4
Monster Rank 5: Chest Rank 2 to 5
Monster Rank 6: Chest Rank 2 to 6
Monster Rank 7: Chest Rank 3 to 7
Monster Rank 8: Chest Rank 3 to 8
Monster Rank 9: Chest Rank 4 to 9
Monster Rank 10: Chest Rank 5 to 9
Monster Rank 11: Chest Rank 1 to 10
Monster Rank 12: Chest Rank 4 to 10
Again, which rank a specific chest will be is randomly determined within the range, but is based on the map's random seed so that it will always be the same rank between visits.
Finally, when you open a chest, you will receive a random item from a list based on that chest's rank. This is not the same between visits, so you are encouraged to revisit grottos in order to hunt down rarer items from the same lists. What follows is the item lists for each rank and their individual chances. All chances in each list should add up to 100%.
Rank 1 Chests
10% each: 125 gold, Gleeban Groat, Medicinal Herb, Evac-u-bell, Holy Water, Chimaeara Wing
8% each: Strong Medicine, Antidotal Herb, Moonwort Bulb
5% each: Magic Water, Oaken Club
2% each: Pop Socks, Silver Bracelets, Bunny Tail
Rank 2 Chests
10% each: 268 gold, Superior Medicine, Strong Antidote, Angel Bell, Fisticup, Iron Nails
8% each: Gleeban Groat, Lava Lump, Royal Soil, Rockbomb Shard
2% each: Iron Mask, Silver Platter, Gold Bracer, Gold Ring
Rank 3 Chests
10% chance of Cannibox ambush
10% each: 450 gold, Toad Oil, Mini Medal, Gleeban Groat, Fisticup, Iron Ore, Corundum, Resurrock
5% each: Gleeban Guinea
2% each: Strength Ring, Agility Ring
1% each: Slime Shield
Rank 4 Chests
5% chance of Mimic ambush
15% each: Manky Mud, Nectar, Magic Water
12% each: 670 gold, Mini Medal
10% each: Gleeban Guinea
5% each: Flintstone, Mirrorstone
2% each: Sorcerer's Stone
1% each: Fuddle Bow, Glombolero, Saint's Ashes, Malicite
Rank 5 Chests
5% chance of Mimic ambush
15% each: Panacea, Magic Water, Narspicious
12% each: Mini Medal
10% each: Hephaestus' Flame, Finessence, Aggressence
1% each: Brouhaha Boomstick, Thug's Mug, Maid's Mop, Muscle Belt, Maid Outfit, Dangerous Bustier, Toughie Trousers, Thug Boots
Rank 6 Chests
10% chance of Mimic ambush
15% each: Gleeban Guinea, Hephaestus' Flame, Mystifying Mixture
10% each: Mini Medal, Astral Plume, Mythril Ore
6% each: Densinium
1% each: Hela's Hammer, Demon Whip, Oh-no Bow, Hades' Helm, Riotous Wristbands, Fingerless Gloves, Veteran's Gloves, Blessed Boots, Skull Ring
Rank 7 Chests
10% chance of Mimic ambush
15% each: 880 gold, Mini Medal
10% each: Sage's Elixir, Saint's Ashes, Densinium, Lucida Shard
6% each: Perfect Panacea
2% each: Unhappy Hat, Depressing Shoes
1% each: Ruinous Shield, Skull Helm, Veteran's Armour, Divine Dress, Matador's Gloves, Trinity Tights, Veteran's Boots, Combat Boots, Spellspadrilles, She-mage Shoes
Rank 8 Chests
5% chance of Pandora's Box ambush
15% each: 1500 gold, Mini Medal, Gleeban Gold Piece
13% each: Mythril Ore, Enchanted Stone
10% each: Sage's Elixir
5% each: Gold Bar
1% each: Pruning Knife, Hero Spear, Heavy Hatchet, Megaton Hammer, Beast Claws, Wizardly Whip, Attribeauty, Pentarang, Wyrmwand
Rank 9 Chests
10% chance of Pandora's Box ambush
15% each: Mini Medal
10% each: 3000 gold, Gleeban Gold Piece, Sage's Elixir, Astral Plume, Ethereal Stone, Reckless Necklace
8% each: Orichalcum
1% each: Metal Slime Sword, Metal Slime Spear, Metal Slime Shield, Metal Slime Helm, Metal Slime Armour, Metal Slime Gauntlets, Metal Slime Sollerets
Rank 10 Chests
15% chance of Pandora's Box ambush
15% each: Sage's Elixir
10% each: Gleeban Gold Piece, Evac-u-bell, Sainted Soma, Reset Stone
8% each: Yggdrasil Leaf
5% each: Gold Bar, Orichalcum
1% each: Stardust Sword, Deft Dagger, Poker, Bad Axe, Groundbreaker, Knockout Rod, Dragonlord Claws, Gringham Whip, Angel's Bow, Critical Fan, Meteorang, Bright Staff