7. Flash from Oak's aide
Route 2.
Walkthrough
Before going on to Pewter, look for the building on Route 2's east side. One of Professor Oak's aides waits there.
If you own at least 10 kinds of Pokémon, he gives you 
HM05 (Flash). Good places to
fill the Pokédex so far are Route 1, Route 2, Viridian Forest and Route 22.
Flash lights up dark caves. You will not need it until Rock Tunnel, but it is worth taking now.
Also passes through
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