Go to Evergrande City to beat the Elite Four
somebody gives it to us after beating the 8th gym
Go to Sootopolis.
sootopolis city
i go to mossdeep city
in the fortree city
Wallace he was the former 8th gym leader in ruby and sapphire
In Sootopolis City.Trainers and Gym Leader uses Water-Type Pokemon.
TM 26 (Earthquake) is a reward for beating the 8th Gym Leader in Viridian City
The only way to get a gym badge is to challenge the corresponding gym leader and win.
You can get the HM waterfall in Pokemon Diamond and Pearl by beating the 8th gym leader and talking to Jasmin by the little beach. She will give it to you.
It's in the gym when you're done defeating the leader he will give you the TM (8th badge)
after beating the 8th gym leader go to the beach and the lady will give you the HM 7 waterfall