yes you can
go to Pokemon and press a Pokemon then press shift
As a Swarm, you can get them on Route 26 while surfing.
you can find it while surfing in the safari zone. there is only a 1% chance though. it would be easier to catch a dratini while surfing.
Psyduck can be found in the Safari Zone while surfing.
In the darker patches of waters while Surfing.
Make all your Pokemon faint while battling Giovanni
Find it while surfing or fishing with the super rod in most water areas.
Wailord is an immense Water type Pokemon. It can be encountered in the wild in Pokemon Sapphire while Surfing on Route 129.
Spheal can be found in Undella Bay while surfing during the winter.
Yes you can, but only if you have a level 40- Pokemon on the front of your team
You cannot use a potion when battling an opponent because the potion hasn't been programed to work yet in Pokemon crater. You can use it while battling wild pokemon.
By battling other pokemon, use rare candy, or by putting the in the day care for a while.(note: if you leave a pokemon in the daycare for a while they may forget some moves you taught them)