Portals are a mechanism by which player characters can transition from one place to another, often thought of as a magical door or rip in reality (as opposed to a normal door or edge-of-the-region transition). Portals are usually accessed by using a placeable.
There are various ways to classify portals. From a player' s perspective, there are four major types of portals, distinguished by their in-game effects. Some portals are transitions within an area, in which case associates might be left behind (depending on the script being used). Other portals lead from one area to another within a module, in which case associates will follow the PC. Portals can also lead to the next module in a campaign, in which case all non-henchman associates are (almost surely) lost, and henchmen only accompany the character if the module's author specifically made allowances for that. In addition, in a multiplayer game, if one character causes a transition to the next module, then all players make that transition (the server ends the old module and starts the new one). Finally, in a multiplayer setting, it is possible to have a portal lead from one server to another. These fate of associates are much the same as with inter-module portals (perhaps with a lower chance of henchmen making the transition), but in this case other players are not necessarily forced to also traverse the portal.
From a builder's perspective, the first two types of portals (intra- and inter-area) are created the same way, with a script that jumps characters to some target object (or location). The inter-module portals are created by starting a new module, while inter-server portals require calling ActivatePortal().
Server portals[]
Server portals are created when one server operator requests a link and another server operator accepts. This will form a two-way transfer between the two servers, allowing players to travel between the two worlds simply by stepping through the portal. Once a portal is created, it remains until removed by one of the server operators. If the server on the other end is currently not operational, the portal will appear closed. Players can view a wide variety of information about the server on the other end by inspecting the portal. If the character does not meet the requirements of the new server, the player is not teleported and re-appears beside the original server's portal. Servers can support multiple portals.
The implications of this portal system are extensive. By distributing different areas and population load over a number of home computers with decent Internet connections, for instance, a gameworld can know no boundaries. On a smaller scale, two rival player guilds could agree to portal their guildworlds together to settle a dispute in battle. Freewheeling MUDs and MUSHes could also emerge where people cobble their different creations together into a larger, cosmopolitan world of adventure. BioWare envisioned multiplayer Neverwinter Nights as a means of getting people together, and portals allow that to happen on a grander scale.