Rifts are random encounters in the real world- a spawn of monsters from one of six planes. If players don't seal the rift, they expand and invade your territory. They are a great alternative to questing or warfronts. Here are some images from life rifts that happened today.
You can spot a rift by the telltale visual effect in the sky- you can also see them on your map. This one is a life rift, opening behind me.
Looking up into the rift forming in the air. A rift is a disruption in the world, caused by an intrusion from another plane of existence. The node sprouts tendrils that reach towards the ground, 'infecting' the area and the creatures therein.
At first, the rift is small. Players start to gather around the vortex. If players don't close it promptly by defeating the initial invaders, the rift will grow and expand.
Here's a foothold or an invasion force sent out from a big rift to attack areas nearby. These guys can hit hard.
Magic effects wash over the players. Rifts are dynamic public quests that form spontaneous raid groups for the participants, so no one has to organize them. A raid interface will pop up if you so desire. The sounds of a rift can startle and scare you; it is a very atmospheric experience.
A life rift spreads- notice the exotic otherworldly vegetation starting to grow.
Fighting.
There are separate stages in the rift encounter, varying from multiple opponents to big bosses.
This life rift opened near a town. Rifts can open anywhere.
The vortex flares as the monsters are defeated.
Victory! Loot is distributed to each player individually via the UI, and can include many items.
