Chalice Dungeon Multiplayer Information
In order to Co Op a Chalice Dungeon you must have created the Chalice of that Dungeon yourself at least once. You CANNOT join Chalice Dungeons that are using Chalices you have not yet acquired and made.
You can Co Op with a friend by giving them your Chalice Glyph or by them giving you theirs and entering it in at a Ritual Altar in Hunter's Dream.
All Chalice Dungeons can be Co Oped, but only some can be PvPed. In order for PvP in a Chalice Dungeon, the player must have created or joined a Dungeon that was made using a Root Chalice or a Sinister Chalice. There is one Sinister Chalice of each type: Pthumeru, Hintertomb, Loran and Isz.
You can set a chalice dungeon to shared and closed, and only people with the glyph will be able to PvP or Co Op. However they will need to manually move to the location of the host, requiring them to clear the dungeon.
It is important to remember that only the host's progress is saved, so in order to clear the entire dungeon you will have to take turns hosting and being summoned. Summoned players vanish after each boss is defeated.
Once you have defeated the last boss of the Lower Hintertomb Chalice, you will receive the Short Ritual Root Chalice which can be used at the Makeshift Altar in Hunter's Dream. This will allow you to quick search for Chalice Dungeons to join as the guest, host or invader. You can use the Short Ritual Root Chalice Co-Op search feature with a password (to help connect to the desired target) to be summoned in their dungeon at ANY layer they are in. Whatever chalice they are in gets placed at the Makeshift Altar, granting you a FREE dungeon to go through from the start if you wish. You can remove the chalice that is placed in the Makeshift Altar and begin your Co-Op search anew for any other people who you may want to help. In addition Co-Op through the SRRC method has a chance of placing you in a completely random room of the dungeon. In order for this to work the Chalice Dungeon must be SHARED AND OPEN (not Closed)