As you can see there are 5 areas of Phantasm Island. All Spirit bosses drop: b-dai, n-zel, n-dai, haste pot, ghaste pot, pine wand, maple wand, ebony wand, rings, necklaces, blue pot, magic gem, b-res, res scroll, adena and braves.

Area A is a water-themed area. The Great Spirit of Water is escorted by Ice Man and Ice Golem. Ice Golem breaks swords, so make sure you bring whetstones here.

Area B is the fire-themed area. The Great Ball of Fire is accompanied by fire eggs and salamander. You will also will find fungus, be careful, these aren't elven dungeons fungus - in fact, you can lose 30HP/tick when poisoned, so bring twigs.

Area C is the earth-themed area. Here you'll find the Great Spirit of Earth as well as Crazy Rabbits and Guardian Armor, which is only weak to magical attacks. Knights can't really do well here, but mages that tame scorpions can hunt here.

Area D is the wind-themed area. You'll find the Great Spirit of Wind as well as Killer Bee and Ball Lightning. These things are believed to be bad at dropping adena and items, so it is considered a waste of potions to hunt. The Wind boss spawns near the ends of the zone and their tornado can hit for up to 400 HP.

Area E is a "neutral" area. At a rare spawn rate, you will find a Unicorn, which, if you cancel it, will yield Nightmare, a very strong boss. Nightmare drops Cloak of Invisibility and other very expensive items.

Throughout the island you'll have the opportunity to drop Dreamweaver, which drops the elixir. Dreamweaver can hit for 400HP in a single shot, but that kind of risk might be worth it, since an elixir could give you a permanent +1 to your base stat..