You have to go to route 2 after you have gotten cut. Then you place the pokemon who knows cut where the small tree is. After you beat the level Prof. Oak should come out and give you flash. I hope I helped!
Use flash. At the end of Digletts' Cave you find Cut. Teach Cut to a pokemon and go to route 2. Place the pokemon that has cut next to the small tree and make it use cut. At the end Prof. Oak will pop out and give you flash. Teach flash to a pokemon and put it in your party. Don't worry this time, you will not have to set it on flash.
You have to get flash. Go trugh the diglett cave in the city with that boat. Then straight down
get the HM05 FLASH
you defeat him with a powerful pokemon
go up 3 times and turn left
go up twice then turn left
go past rock tunnel
To navigate through Rock Tunnel
On the map, yes the power plant is by the Pokemon Tower. However, the Power Plant is on the northern side of Rock Tunnel. From the northern entrance of rock tunnel, surf south past the mountain until you find land. The Power Plant is located here.
Rock Tunnel (Uncommon) and Route 10 (Uncommon).
use the move Flash (TM70)
Go to Rock Tunnel at Cerulean City(maybe I spelled it wrong) there would be a boy in there with the yellow hat will teach one of your Pokemon(you have to have a Pokemon that is a rock type)
go there lol yea u do go there but you have to go through rock tunnel
when you get cut teach it to a pokemon in your party and go back and beat route 2 and professor oak will give you flash the go to rock tunnel with a pokemon that know flash and it should light up and the onix will be gone
Go to the pokemon centre at rock tunnel and surf southwards. Rock tunnel is east of cerulean.
In order 2 get to rock tunnel u need 2 have cut.u go 2 the east of cerulean city and use cut at the tree.go beat all the trainers and find the right way.
Get Flash from a guy a route 2 Get Flash from a guy on route 2
it's past mount moon but not past rock tunnel keep going. watch for trainers they can get annoying.when you see water ride on it