25 February 2026

HM05 Flash Location in Pokemon FireRed & LeafGreen

By newsgame


HM05 Flash is a move that can help trainers light up dark caves like the Rock Tunnel when it is used outside of battle in Pokemon FireRed and LeafGreen. While navigating these dark caves without using Flash is certainly possible, it can be extremely tedious.

This guide covers the exact location where players can find HM05 Flash in FRLG, how to use it outside of battle, and the best HM slaves that can be taught this move. Here are the details.

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How to Get Flash in Pokemon FireRed and LeafGreen

HM05 Flash Location

HM05 Flash pokemon firered leafgreen Image via GameRant; Source: Bulbapedia

  • Requirements: HM01 Cut, 10 different Pokemon species captured

HM05 Flash can be obtained by talking to Professor Oak’s Aide on Route 2 after having captured 10 species of Pokemon in Pokemon FireRed and LeafGreen. Route 2 is located south of Pewter City, but the eastern part of this route is blocked by trees that can only be cut down using HM01 Cut.

HM05 Flash is mainly needed to light up the interior of the Rock Tunnel on Route 10. If this is your starting point, the fastest way to return to Route 2 near Pewter City is by going through the Diglett’s Cave east of Vermilion City.

vermilion city HM05 Flash location in pokemon firered leafgreen Image via GameRant; Source: Bulbapedia

To go there from Route 10, first return to Cerulean City through Route 9. Then, head south to Route 5, and go through the Underground Path next to the Day Care to reach Vermilion City via Route 6.

route 11 HM05 Flash location in pokemon firered leafgreen Image via GameRant; Source: Bulbapedia

From Vermilion City, take the eastern exit and you’ll immediately come across Diglett’s Cave.

The Diglett’s Cave is crawling with Diglett that have the Arena Trap ability, which prevents you from running from battles. Either use a Repel or lead with a Rattata that has the Run Away ability.

digletts cave HM05 Flash location in pokemon firered leafgreen Image via GameRant; Source: Bulbapedia

Go all the way through the Diglett’s Cave, and when you exit, you’ll find yourself on Route 2 (East).

HM05 Flash location in pokemon firered leafgreen Image via GameRant; Source: Bulbapedia

From here, head south and cut down the tree using HM01 Cut. Enter the building to the south, and you’ll see Professor Oak’s Aide inside.

HM05 Flash location in pokemon firered leafgreen (2) Image via GameRant; Source: Bulbapedia

Talk to him, and he’ll confirm whether or not your Pokedex has complete data on ten species of Pokemon. If it does, he will reward you with HM05 Flash.

If you have access to HM02 Fly outside of battle, simply Fly to Pewter City, head south to Route 2, and cut trees to the east to reach the building with Professor Oak’s Aide.

How to Use Flash in Pokemon FireRed and LeafGreen

how to use flash in pokemon firered leafgreen Image via GameRant; Source: Bulbapedia

Flash is used to light up dark interiors, revealing the layout of caves covered in darkness. The Rock Tunnel on Route 10 is the main location where Flash is useful in FRLG. Although you can traverse the Rock Tunnel without Flash, it is extremely inconvenient and disorienting to do so.

To use Flash, you’ll first need to teach it to a Pokemon who can learn the move and place it in your party. Once you’re in a dark location that can be lit up using Flash, open the pause menu, go to Pokemon, and select the Pokemon that you taught Flash to.

Select the blue Flash text from the context menu, and your Pokemon will use the move to light up the cave. For as long as you do not leave the cave, Flash’s lighting effect will remain active. If you leave, you’ll need to reapply Flash when you return.

Best HM Slaves for Flash in Pokemon FireRed and LeafGreen

Best HM Slaves for flash in Pokemon FireRed and LeafGreen Image via GameRant; Source: Bulbapedia

It can be troublesome to find a Pokemon that can use Flash in Pokemon FireRed and LeafGreen. Since it is almost entirely useless in battles, you definitely do not want any of your core team members to waste a move slot on this move. The following are the best HM slaves that can learn Flash:

  • Pikachu
  • Oddish
  • Paras
  • Meowth
  • Psyduck
  • Abra


Pokemon FireRed and LeafGreen Tag Page Cover Art

Systems


Released

September 7, 2004

ESRB

e

Publisher(s)

Nintendo