Geralt is always reachable by the network. Unless it's an emergency, expect not to hear back for a few hours, if not a few days.
To talk to him in person, you'll need to be in Cadens or go to his domain, a snowy mountain fortress. Yard is open; doors are locked. If he isn't around, leave a delivery with the white wolf.
FAIRYTALES ALL STARTED SOMEWHERE AND UNFORTUNATELY FOR US THE WHOLE 'REALITY VS. FAIRY TALE' ARGUMENT DOESN'T REALLY WORK NOT WITH THE THINGS WE'VE SEEN
I GUESS THAT'S WHAT I'M TRYING TO WRAP MY HEAD AROUND IF ALL SUMMONED ARE ON A PATH TO GET MORE AND MORE POWERFUL GOD-LIKE, IF WE WANTED TO GO THAT FAR THEN THE PEOPLE WHO'VE SUMMONED US HERE ARE BEYOND HUBRIS IT'S NEARLY SUICIDAL AND WE HAVEN'T HAD ANY MORE ACCOUNTS OF ANYONE TRYING TO USE SUMMONED MAGIC LIKE WE DID BACK IN THORNE, RIGHT? CAUSE I HAVEN'T HEARD OF ANY
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