The Lake of Rage (Japanese: いかりのみずうみLake of Rage), also known as Gyarados Lake (Japanese: ギャラドスこGyarados Lake), is a location in Johto. It is located just north of Mahogany Town, connecting it with Route 43, making it the northern-most accessible point of the Johto region. A large lake spans the area of the Lake of Rage, with a few residents living nearby. It is said to be the largest lake in the region. West of the lake lies a labyrinth of trees, which hides a house.
It is said the Lake of Rage was created the last time many Gyarados got together and stirred up a storm. The crater that remained filled with rainwater and became the Lake of Rage. In the middle of the lake dwells a ShinyGyarados that had recently became irritable due to the radio waves transmitted by Team Rocket from their hideout in Mahogany Town. The Lake of Rage was considered a dangerous place to go, as the red Gyarados started tipping over boats and scaring swimmers.
In Pokémon HeartGold and SoulSilver, it will rain at the lake every day. After catching, defeating, or fleeing from the Gyarados, it will not rain on Wednesday, and the water level will drop. Different items are accessible and different Trainers appear depending on the weather.
To the northwest of the lake, there is a house hidden within a labyrinth of trees. Inside, a man will give players TM10 (Hidden Power) for locating the reclusive house. The path to this house begins in Route 43, on the western side. In Generation II, crossing the lake is not required, but it is the opposite in Generation IV, as the house is only reachable when the Lake is flooded. On Wednesdays, Wesley is found near this house, and will give the player a Black Belt the first time they meet, and then a Downcast Ribbon every week after having met all seven siblings (Generation IV only).
Southeast of the lake is another house, where a Fishing Guru resides. His greatest dream is to see the world's largest Magikarp, and he regularly measures those brought to him in order to realize it. If he is shown a Magikarp, he will calculate its size and give the player an Elixir if it is bigger than the largest one he had seen before. Initially, this record is 3'6" and held by Ralph.
The player can also Fly to the Lake of Rage; in Generation II, it is the only destination in any game that can be flown to where the player will not land in front of a building, but in Pokémon HeartGold and SoulSilver, the player lands in front of the Fishing Guru's house.
Normal Lake appearance (top) and flooded appearance (bottom) in Generation IV
The Lake of Rage, referred to as Lake Rage in the anime, appeared in Talkin' 'Bout an Evolution and Rage Of Innocence. Ash, his friends, and Lance learned that Team Rocket was conducting experiments at the lake as a part of Project R, which involved forcing Pokémon to evolve. Since the Red Gyarados was the only Pokémon in the lake to have been affected by their experiments, Team Rocket captured it for further studying. However, their project ended in a failure when Lance destroyed Team Rocket's research facility at the lake, followed by the Red Gyarados escaping and getting caught by Lance.
The Lake of Rage appeared in The Lake of Rage. Lance had briefly encountered and battled the Red Gyarados before at the lake, motivating him in investigating the Team Rocket HQ in Mahogany Town. After the radio wave generator that had forced Gyarados to evolve had been destroyed, Lance revisited the lake to see that the Red Gyarados had calmed down.
The Lake of Rage first appeared in Raise the Red Gyarados, where Silver came to inspect it per Lance's instructions, followed by Gold. The two were soon attacked by a swarm of Gyarados. Based on the static on their Pokégear screens, Silver deduced that a radio wave was behind the lake's Magikarp evolving and the Gyarados rampaging. Eventually, Silver managed to locate the source of the radio waves, a Red Gyarados, and proceeded to capture it with Gold's help, stopping the radio waves. However, they were then approached by the Masked Man.
In Delibird Delivery - 1 and 2, Gold and Silver battled against the Masked Man, with Silver using his newly caught Red Gyarados to command the lake's other Gyarados to attack him. Despite this, however, both Gold and Silver suffered a crushing defeat.
In Raising Raichu and Do-Si-Do with Dodrio, Lt. Surge arrived at the Lake of Rage to investigate Gold and Silver's disappearance. Using his submarine, he dived into the lake and found the Red Gyarados frozen in ice, as well as some of Gold and Silver's belongings.
A possible prototype of the Lake of Rage
Unused debug text in Japanese Crystal spells the lake's name as 「イカリのみずうみ」, with ikari in katakana (イカリ) as opposed to the usual hiragana (いかり). Additionally, there is a leftover map in Gold and Silver that includes a Pokémon Center, Poké Mart, and even a Pokémon Gym surrounding a lake that is a similar size and shape to the Lake of Rage.
Even though it is said that Team Rocket's radio signal is evolving all the Magikarp in Lake of Rage, Magikarp can still be found there at any time. Even if the radio signal is being listened to on the Poké Gear, Gyarados do not show up more often.