yes, emerald is combatible with the wireless adapter...
but it is not compatible with the built in wireless in the Nintendo DS
You have to get the Aurora tickett by the wireless adapter if u have one.
you use it for catching Pokemon but you need a wireless adaptor (emerald version)
The emerald doesn't exist just the ruby and sapphire, to trade with emerald and leafgreen you need two wireless adapters.
Actually, you can't there are none. I'm pretty sure the cave was just something Game Freak did to play with their wireless adapter more; perhaps it would be a place where you could interact with other people with the wireless adapter in. That would make sense, because the cave also appears in emerald after you beat the Pokemon league. Otherwise, nobody really knows what it does.
The way you get waterfall is by trading the waterfall HM from Fire Red Version or the other Version that have waterfall HM ( you can trade with a link cable or wireless adaptor)
No. In Pokemon Emerald Version, you can only obtain Pokemon from generations 1, 2 and 3.
You can up stairs in the pokemon centre if you have a wireless adapter or if you connect with your friendwith a wire unless you play it on ds then u can't Hope i helped
Red version was not made to migrate with emerald.
you have to get it in the Nintendo event or use a wireless adapter to get the mystery gift working and the event will be right in your mystery gift. You will continue talk to a guy and he will give you the event items
No.
NO you can not play Pokemon emerald in Coloseum.
Simply attach it to the top of your GBA if another GBA close by has one as well you can use them to trade Pokemon in firered version, leafgreen version and emerald version. That unfortunately was its only use.