I would say 30-50 for each player should be fine
To trade Pokemon from Pokemon Crystal version to another version of Crystal you need to use a link cable. You can also battle this way.
what do you need to do to frighten evil spirits away
i think 20 berries
Cannot answer without knowing type of crystal and either its mass or size.quartz crystal, nonesugar crystal, nonesalt (sodium chloride) crystal, nonecalcite crystal, need to know either mass or sizeice crystal, noneselenite crystal, need to know either mass or sizeetc.
None.
as many as you need.
3 dumbell
You only need one pokémon to be able to battle against another trainer.
u do not need a crystal to catch kyogre, trust me. simply, when the time has come find sootopolis city and go into the cave of origin. go trhough the levels, then you will battle some people then you can catch kyogre.
ALL 101
If you've already won the battle against Red, you may re-challenge him by first beating the Elite 4, and climbing Mt. Silver again. [Heart Gold, Soul Silver] In the original Gold, Silver, and Crystal, you do not need to beat the Elite 4 again. All you have to do is climb Mt. Silver, as many times as you want, and re-battle him. [Original Gold, Silver, Crystal]
Crystal Radios don't need a power source because, the crystal runs on the radio waves it receives.