Economy: Shards
There are four ways: shop NPCs, the Bazaar for raw materials, the auction for special items, and safe trade with a player.
Shop
The sellers at spawn buy and sell everything. They pay 85% of base value and charge 115%; prices are dynamic: what is sold a lot gets cheaper, what is bought a lot gets dearer. Each item has a daily quota, beyond which it sells at a lower price.
Bazaar
/bazaar (bz): an order book for raw materials. Instant buy/sell, or place an order at your own price. A 2% tax is taken on sales; the open order limit grows with island level. No trades between accounts on the same network (IP).
Auction house
/ah: sell special items, enchanted items and spawners; no bidding, you set the price. Listing fee 2%, sales tax 5%. Raw materials go to the Bazaar.
Safe trade
/trade: two players within 16 blocks or on the same island swap items and Shards; both confirm, a countdown runs, and any change resets confirmations. No trading inside a household.
Fishing contest
Every 150 minutes or so, lasting 10 minutes; the top three catchers get rewards.