Metal King Slimes Only

There are total 19 maps, in 21 rank-seed combinations, about the MKS-only.

Water MKS-only has the weakest support monsters which is very suitable for MC solo leveling up (for earning all vocations's 10-revocate accolades).
Fire MKS-only's support monsters are slightly weaker than Caves but far stronger than Water.
Cave MKS-only has the strongest support monsters but only Caves has the fastest one.

Water
Support Monster Mercy user's Lv ATK
Gigantes 37 212(C)
Genie Sanguini 40 89(C+)
Charmour 45 171
Moai Minstrel Cannot be Mercy-ed 368
Slugly Betsy Cannot be Mercy-ed 404
Fire
Support Monster Mercy user's Lv ATK
Drakulard 47 203
Flamin' Drayman 73 416
Terror Troll 73 454(C)
Tantamount Cannot be Mercy-ed 358
Barriearthenwarrior Cannot be Mercy-ed 432(C)
Caves
Support Monster Mercy user's Lv ATK
Cosmic Chimaera 84 378
Wishmaster 84 513(C+)
Cumulus Hex Cannot be Mercy-ed 462
Octagoon Cannot be Mercy-ed 420

C: Critical Hit
C+: Critical Hit (through character's defense)


Index

Sapphire Nest of Joy Lv.55
Silver Nest of Doubt Lv.55
Silver Marsh of Bane Lv.58 (Water)
Emerald World of Woe Lv.64 (Fastest)
Diamond World of Regret Lv.65
Emerald Abyss of Glee Lv.69
Bronze Abyss of Fear Lv.76
Bronze Abyss of Dread Lv.77
Bronze Crypt of Hurt Lv.77
Gold Abyss of Hurt Lv.79
Silver World of Dread Lv.79
Steel World of Dread Lv.79
Bronze Abyss of Dread Lv.80
Bronze Nest of Hurt Lv.82 (Fire)
Bronze Crypt of Dread Lv.84
Emerald Path of Fear Lv.84
Ruby Path of Doom Lv.87
Gold Abyss of Ruin Lv.91
Steel World of Evil Lv.94 (Fire)


Sapphire Nest of Joy Lv.55
Location: Eastern Wormwood (94)
Map: Caves
Monster Rank: 8~11
Boss: Equinox @ B16
Chest: A2 B4 C7
Details: MKS-only @ B12.

Silver Nest of Doubt Lv.55
Location: Eastern Wormwood (69) / Urdus Marshland (52)
Map: Caves
Monster Rank: 8~11
Boss: Nemean @ B14
Chest: S2 A2 B2
Details: MKS-only @ B9 (1m 40s).

Silver Marsh of Bane Lv.58 (Discoverer: ranka … etc. / aro- … etc. / hatuko … etc.)
Location: Mt Ulbaruun (5D) / Western Coffinwell (8A) / Wormwood Canyon (73)
Map: Water
Monster Rank: 6~8
Boss: Elucid @ B12
Chest: C1 D6 E1
Details: MKS-only @ B11 (2m 43s). The only Water-MKS map in the game. Water-MKS has the weakest support monsters in all MKS-only maps.

Emerald World of Woe Lv.64 (Discoverer: yosiyuki … etc. / masahiro … etc.)
Location: Western Stornway (07) / Angel Falls (86)
Map: Caves
Monster Rank: 9~12
Boss: Nemean @ B17
Chest: A4 B9 C2
Details: MKS-only @ B8 (1m 17s). The fastest MKS-only map.

Diamond World of Regret Lv.65
Location: Western Wormwood (6D) / Angel Falls (04)
Map: Caves
Monster Rank: 8~10
Boss: @ B13
Chest: A3 B2 C6
Details: MKS-only @ B12. There's a chamber on the MKS floor.

Emerald Abyss of Glee Lv.69
Location: Angel Falls (86) / Western Wormwood (6F) / Western Stornway (06)
Map: Caves
Monster Rank: 8~11
Boss: Nemean @ B17
Chest: S2 A2 B4
Details: MKS-only @ B11 (2m 32s). There's a chamber on B7.

Bronze Abyss of Fear Lv.76
Location: Zere (0E)
Map: Caves
Monster Rank: 7~10
Boss: Hammibal @ B17
Chest: A1 B3 C4
Details: MKS-only @ B15.

Bronze Abyss of Dread Lv.77
Location: Djust Desert (35) / Newid Isle (1E)
Map: Caves
Monster Rank: 7~10
Boss: Atlas @ B16
Chest: A2 B2 C3
Details: MKS-only @ B13 (3m 19s).

Bronze Crypt of Hurt Lv.77 (Discoverer: rikuretu … etc. / siina … etc.)
Location: Newid Isle (1E) / Western Stornway (07)
Map: Caves
Monster Rank: 8~10
Boss: Fowleye @ B13
Chest: A2 B2 C3
Details: MKS-only @ B9 (1m 43s).
You can get a Hero Spear (which can recover your character's HP by defeating MKS) on B8 by Quicksave & Quickload.

Gold Abyss of Hurt Lv.79
Location: Urdus Marshland (51) / Wyrmsmaw (7E)
Map: Caves
Monster Rank: 7~10
Boss: Hammibal @ B15
Chest: A1 B4 C5
Details: MKS-only @ B14 (3m 13s)

Silver World of Dread Lv.79 (Discoverer: nao … etc. / gureison … etc.)
Location: Eastern Wormwood (69) / Urdus Marshland (52)
Map: Caves
Monster Rank: 8~11
Boss: Hammibal @ B16
Chest: S3 A2 B3
Details: MKS-only @ B9 (1m 40s).

Steel World of Dread Lv.79
Location: Urdus Marshland (4E) / Lonely Coast (31)
Map: Caves
Monster Rank: 7~10
Boss: Hammibal @ B17
Chest: A4 B4 C2
Details: MKS-only @ B16.

Bronze Abyss of Dread Lv.80
Location: Djust Desert (35) / Newid Isle (1E)
Map: Caves
Monster Rank: 7~10
Boss: Hammibal @ B16
Chest: A2 B2 C3
Details: MKS-only @ B13 (3m 19s).

Bronze Nest of Hurt Lv.82 (Discoverer: … etc. / aruma … etc. / toruneko … etc.)
Location: Snowberia (47) / Wyrmtail (74) / Mt Ulbaruun (5D)
Map: Fire
Monster Rank: 7~10
Boss: Excalipurr @ B17
Chest: A4 B2 C1
Details: MKS-only @ B10 (2m 8s). The fastest Fire-MKS map.

Bronze Crypt of Dread Lv.84 (Discoverer: ayumi … etc. / … etc.)
Location: Western Stornway (08) / Eastern Stornway (87)
Map: Caves
Monster Rank: 8~11
Boss: Excalipurr @ B15
Chest: S2 A2 B4
Details: MKS-only @ B9 (1m 48s). There's a chamber on the MKS floor.

Emerald Path of Fear Lv.84
Location: Angel Falls (86) / Western Wormwood (6F) / Western Stornway (06)
Map: Caves
Monster Rank: 8~11
Boss: Fowleye @ B15
Chest: S2 A2 B4
Details: MKS-only @ B11 (2m 32s). There's a chamber on B7.

Ruby Path of Doom Lv.87 (Masayuki Map) (Discoverer: … etc. / masayuki … etc.)
Location: Eastern Wormwood (6B) / Iluugazar Plains (54)
Map: Caves
Monster Rank: 7~10
Boss: T-wrecks @ B16
Chest: A1 B6 C5
Details: MKS-only @ B15 (3m 53s). It's also used for Map Method Seed Farming.

Gold Abyss of Ruin Lv.91
Location: Urdus Marshland (51) / Wyrmsmaw (7E)
Map: Caves
Monster Rank: 7~10
Boss: Excalipurr @ B17
Chest: A2 B5 C6
Details: MKS-only @ B14 (3m 13s)

Steel World of Evil Lv.94
Location: Western Coffinwell (68) / Urdus Marshland (51)
Map: Fire
Monster Rank: 6~9
Boss: Greygnarl @ B17
Chest: B2 C6 D6
Details: MKS-only @ B15. One of the only two Fire-MKS map.