A Portal is a magical passage that will teleport you another area.
Mechanics
Portals, like Waypoints, transport the player to another location. One key difference between them is that Waypoints can only teleport the player to areas that he/she has already been to, while portals are sometimes the only way to new or inaccessible areas.
Portals can be either blue or red.
Blue Portals
Diablo 2 Blue Portal
Blue portals are always Town Portals, and thus give access to the Act's respective towns. They can be summoned by experienced mages as well as non-experienced players by use of a Scroll of Town Portal.
Once the player summons this portal, it only dissipates if the player that cast it goes through and returns. So it is very useful in co-operative play to have 2 party members create portals so that the entire party can go back to town, to heal and repair. Just make sure that the players who summoned the portals go through each other's portals and not through their own portal.
Red Portals
Red Portals are more powerful and permanent portals which never dissipate unless their use is finished.
Diablo 2 Red Portal
They link many inaccessible areas in the world of Sanctuary.
This is a list of all the areas linked by Red Portals:
Diablo
- Unholy Altar (This is the only red portal in diablo 1)
Diablo II
- Tristram (This is the first red portal seen in diablo 2)
- Canyon of the Magi
- Pandemonium Fortress
- Harrogath
- Abaddon
- Pit of Acheron
- Infernal Pit
- Nihlathak's Temple
- Moo Moo Farm
It may useful to know that the portal to Nihlathak's Temple will not close unless the Waypoint at the Halls of Pain is activated. This may be useful to run Pindleskin, a unique monster famous for high level drops.
The portal to the Pandemonium Fortress is a special portal because it was summoned by the Prime Evils themselves. Otherwise, it is just another red portal. Similarly, the portal to Harrogath is summoned by Tyrael and disappears when the Waypoint at Harrogath is activated.
The portals to Abbadon, the Pit of Acheron and the Infernal Pit are extra areas that can be used for levelling up and item hunting.
The portal to the Moo Moo Farm is created by transmuting a Tome of Town Portal with Wirt's Leg in the Horadric Cube. It gives access to the Secret Cow Level.