Rifts appears randomly and rarely near the player that come from a different dimension and spawn waves of monster you’ll have to kill and when you clear them a boss appear and give you great reward upon killing him.
when you look at the sky while inside the rift you can see the other dimension where the creatures come from and when you kill the final boss the rift is sealed.
I think some players are just unlucky to find dungeon and bosses and they get a little frustrated so I think the rift system holds a lot of potentials in it.
Also in many sandbox games the monsters there are pretty weak and doesn’t cause a threat to your life as much as falling -.-, players should hide at night because of the danger await them outside, when a person at night look outside his walls and see giant titans walking around and dangerous creatures walk around them, they will lock their doors for sure.
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