Happiness Lake

Happiness Lake, also called HL, is a dungeon in PMU 7 that is stronger than Seaside Cavern and Tiny Grotto. It is found in Exbel. The dungeon here is full of Water types and is the first, in order of difficulty, to introduce type-only tiles. This dungeon has 7 floors.

The Pokémon in this dungeon are mainly in the level range of 7-14, but Magikarp are level 1.

Low Floors
The low floors in this dungeon have small rooms. The ground itself is covered with grass, with stone/mud walls being a light tan color. The water is common. This lasts from the beginning to floor 5.

Upper Floors
The upper floors are like the lower floors, however water becomes common to the point where there is more water than ground. The walls become disjointed and are scattered throughout the floors. There is also a darkness that is added to the dungeon. This lasts from floor 6 to the end.

Lower Floors
The Pokémon here are mainly Water or Bug types. They are all first evolutions and have low level.
 * Lotad
 * Oddish (Dusk & Night)
 * Poliwag
 * Yanma (non-Night)
 * Bidoof
 * Farfetch'd (time based, dawn)
 * Wooper (dawn, dusk?)*

Upper Floors
The Pokémon are the same as before, only now Magikarp has been introduced. It only knows the move Splash. * Only attacks in self-defense
 * Magikarp
 * Lotad
 * Oddish
 * Poliwag
 * Yanma
 * Bidoof
 * Farfetch'd (time based, recruitable?)
 * Ducklett (eggs in water, 6-7F)

Items
The items in this dungeon are what is necessary for an explorer to complete the dungeon. This dungeon is also the first in terms of difficulty to introduce a weather-manipulating orb. At the end of the dungeon, there is a single room with very limited visibility. This room contains a single box as a prize for completing the dungeon as well as Poke around the edges. This is where the Water types come in handy if you're looking for a quick 75 Poké (around the edges). The items that you can get from the box are as follows;
 * Apple
 * Long Onion, Rare (Farfetch'd Drop)
 * Geo Pebble
 * Oran Berry
 * Pecha Berry
 * Oren Berry
 * Cheri Berry
 * Chesto Berry
 * Tiny Thorn
 * Rainy Orb
 * Warp Orb
 * Warp Seed
 * Slip Seed (only on water?, 6-7F?)
 * Poké
 * Reviver Seed (water 6-7F)
 * Mystic Water
 * Honey
 * Soft Sand
 * Poison Barb
 * Big Apple
 * Max Ether
 * 10 Stick
 * Shed Shell

Mystery Eggs
The eggs can be found on 6-7F in the water. Mystery Eggs contain Ducklett.

Dungeon Objective
The objective in this dungeon is like the others, to go up the floors and beat the dungeon. There is nothing about this dungeon except having Magikarp ant it being a pretty easy way to obtain items and Poke for newer players.
 * If you bring a Water- or Flying-type to the dungeon's endroom, you'll be able to collect Poké that surrounds the lake.

Trivia

 * This is the first dungeon in order of difficulty that has weather manipulating orbs.
 * In PMU 6, this was the easiest random dungeon, and the first completely random dungeon.
 * It is currently the only dungeon to have Magikarp, not including some Holiday Caves.
 * Though Happiness Lake and Sunny Hillside are of approximately the same difficulty level and length, more Poké can be found in Happiness Lake than in Sunny Hillside.