The Portal spell opens a one-way gate in the fabric of reality, by joining the locations of the caster and target. The target can be either a player or a mobile, but not an object or room. A portal will stay open longer for higher-level players, but it will eventually collapse. After the portal has opened, step through to the destination by typing "enter portal". Portal carries a risk of damage to hp and/or mana. Enter unknown portals with caution. It is your responsibility to know which portal you enter.
This spell is invaluable to characters of all classes, especially when running in groups. When portaling, target keywords should be chosen carefully as some are shared by multiple mobs. Scry may be used to verify where a certain combination of keywords will (currently) lead; this destination may change over time, however, as mobs move and die and respawn. See Portals for more information about these objects created by this spell.