There in the gym in mossdeep city by the way the gym leader are actually gym leaders.
The seventh gym leader is Candice, the Ice Type leader. She is at Snowpoint City.
To defeat or "beat" the 7th gym leader in Pokemon sapphire there twins and they have a solrock and a lunatone to beat them I suggest about level 40-50 water types.
Go on to defeat the seventh gym in Mossdeep City, if you did not already catch Kyogre.
sootopolis city, after u awake rayquaza. the gym leader is juan, changed from ruby/Sapphire Wallace
In sapphire, the 5th gym leader is your dad, in that city after Oakdale.
in poo land.
The 6th gym leader in Pokémon Sapphire is found at the Fortree Gym. The name of the gym leader here is Winona.
go right from the seventh gym leader
You have to Dive and then you can battle the Gym Leader.
The 8th Gym Leader in Pokémon Sapphire can be found in Sootopolis City.
You have to surf from Lilycove to Mossdeep city so you can challenge the 7th Gym Leader, The psychic twins, Tate and Liza.
The seventh gym city is in Snowpoint City, you have to go in Mt Coronet and find the way out to route 216 and go to route 16 until you find Snowpoint City. The Gym Leader is Candice the Ice type leader.