Magikarp x6
beat the dome 5 times and that should get you to fight tucker and if you win you get a silver symbol and beat the dome 10 times to get you to tucker and if you beat him you get the gold symbol
You will battle Tucker, the leader as well as the Frontier Brain of the Battle Dome after you beat 5 tournaments consecutively during one-on-one matches only so you will have to beat 19 matches consecutively before Tucker will battle you.
Beat the elite four the cave should open.
how to beat Pokemon emerald
you beat Archie on emerald
you should go look for the legendaries
high leveled legys around level 65
Go outside
well in ruby and sapphire you need to beat all gyms and then beat the elite four then it should be open but in emerald you only need to beat the 8 gyms
there is no events in Pokemon emerald but you can catch it after you beat the elite four then go to the second Pokemon gym and there should be a cave with a guy standing in front of it and mew and mewtwo should be in there hope i helped
Go back to petalburg and battle your dad
You can beat Sorbetti by attacking his red nose. This should be repeated the 3rd time.