You can get timer balls at the rustburo pokemart. that's where my friend and i get ours. they are great for catching legendaries, but you will need a lot of them.
buy at rustborough mart.
Once you help the Devon corp you can purchase timer balls and repeat balls at the rustboro city pokemart.
Rustbourd city
Timer balls can be found in the Pokemart in Rustboro City
You can buy them at the Pokemon mart at the Pokemon league. I buy my timer balls, heal balls, etc. at the Pokemon mart in canalave city
Rustburo. can u only get one?
You could get timer balls by buying them from the store at the Pokemon legaue or helping the man for the newspaper in solceon town.
Timer balls are only in Pearl and Diamond
Timer balls are pokeballs but are more effective the longer the battle has been going.
It is not possible to catch groudon in Pokemon sapphire, in ruby, you must either use your masterball, weaken it and use ultra balls, or use timer balls, although the last one takes a loooonng time.
A timer ball is good to use when you want to catch a Pokemon you've battled for a while. The more turns you have in a battle, the better more chance you have to catch to Pokemon with a timer ball. (I caught my Groudon in Emerald with a timer ball ^_^)
No.