The word sandbox gets attached to almost any online game with crafting or an open map, but those features alone do not create a sandbox MMORPG.
A useful definition starts with agency. In a strong sandbox, players can choose goals that are not simply the next quest marker, and the game’s systems let those choices affect other players or the persistent world. Crafting matters more when other players depend on crafted equipment. Housing matters more when buildings occupy meaningful space. PvP matters more when it changes territory, resources or economic demand.
That is why two sandbox MMORPGs can look completely different. EVE Online has no farming villages or deformable hills, yet its corporations, markets, industry and territorial wars create an enormous player-driven sandbox. Wurm Online approaches the idea from the opposite direction: players literally reshape terrain, build settlements and develop the physical world.
For this database, we classify mechanics rather than relying on a single genre label. Player economy, classless progression, building, settlements, politics, sieges, full loot, open PvP and terraforming are all signals, but no one checkbox is mandatory.
The MMO requirement matters too. A survival game that supports small private servers may be a great sandbox, but it is not automatically an MMORPG. We focus on persistent shared worlds designed around a large continuing community.